75 Gallon Tank Help ... our fish are dying

This is my first tank in over a decade. My first experience was an all glass 26G bow-front that I planted with soil from day one and overstocked from day 2 with a maximum 2 fish per gallon. I couldn't kill anything in that tank for 5 years before moving across country and giving it away. Only had to do water top offs, occasional vacuuming, and change of filter sponges monthly.

Currently jumping back into this I purchased a Vepotek acrylic cylinder system that's 24 inches diameter and 36 inches tall; approximately 70G primary tank and 8G glass sump tank. To start we used 50G hard city water (NV) and the rest was RO we purchased around 20G of and the rest from our drinking system. Our water changes have been 6G RO and the rest hard city water; we were doing 2 changes per week for our first 4 weeks as directed by Aquarium Store. We used a few bottles solution including API Quick Start, API Stress Zyme, Reeflowers. We also placed 10 neon tetra and 4 dwarf Gourami to help with the cycling. Substrate polished rocks thoroughly rinsed; driftwood was boiled several times until no tannin discoloration; plants tied with fishing line and small amount of cyanoacrylate.The first 4 weeks were not an issue. We had ammonia spikes and then nitrate elevations which is why we did the frequent water changes; with additional solutions added to the buckets of water before adding into tank. We had no losses during the 4 week cycle; bacterial bloom in week 2. Only thing we change in the sump is filter sock (every 2-3 days) and filter sponges (weekly). I vacuum weekly so there is no rot under the stones.




Equipment:

• Unicliff 1058gph wave maker (Since the photo was taken we have repositioned the wave maker closer to surface and directed upward.)
• Jerepet 800gpm pump (set to about 60-70% of power because the return flow is not as fast)
• Fluval 32W 24inch LED light
• Hygger Fans (primarily to ventilate the hood and under cabinet)
• Hygger 500W water heater (though I'm not sure its been turning on because the house is warm and before we added it we were at a consistent 78F)
• Air bubbler that came with the tank (Replaced all the other devices as above)

We tested water with our aquarium store and was 0ppm for Ammonia, Nitrite, Nitrate so got go ahead to purchase and added after 4th week (they would not sell us anything before 4 weeks and our "starters" were purchased from Petco):

• 4 Angelfish
• 2 Leopard Cory Cats
• 1 Bamboo Shrimp
• 3 Balloon Rams
• 6 Otocinclus
• Plus the original 4 dwarf Gourami and 10 Blue Neon Tetra

We are currently starting week 9 and we have had some losses weeks 7&8.

1. 1 Cory cat found dead and unharmed in week 7; we had another nitrate/nitrite elevation so we increased water changes and added more bacteria solution
2. 3 Tetra (1 per day) in end of week 7; one of which I found in the mouth of Balloon Ram and then partially eaten in filter sock; another partially eaten in filter sock next day; one never found.
3. 1 Angelfish without injuries start of week 8. By this time we had controlled Ammonia and Nitrites to 0ppm; Nitrates 0-5ppm according to API color chart (using both test strips and solution kit).
4. Yesterday we came home in evening to find one of the Balloon Rams draped over the driftwood gasping. Transferred him to the 3G quarantine tank but he didn't survive long. This was the only one we saw sick before dying and he did not look sick earlier in the day.

All of the fish throughout this setup have been swimming, active, eating, pooping; no signs of distress until this Ram. His color faded, and that black mark under his eye was not there before. A few minutes after the photo he just went belly up. We did not have any medication.

 

This is my first tank in over a decade. My first experience was an all glass 26G bow-front that I planted with soil from day one and overstocked from day 2 with a maximum 2 fish per gallon. I couldn't kill anything in that tank for 5 years before moving across country and giving it away. Only had to do water top offs, occasional vacuuming, and change of filter sponges monthly.

Currently jumping back into this I purchased a Vepotek acrylic cylinder system that's 24 inches diameter and 36 inches tall; approximately 70G primary tank and 8G glass sump tank. To start we used 50G hard city water (NV) and the rest was RO we purchased around 20G of and the rest from our drinking system. Our water changes have been 6G RO and the rest hard city water; we were doing 2 changes per week for our first 4 weeks as directed by Aquarium Store. We used a few bottles solution including API Quick Start, API Stress Zyme, Reeflowers. We also placed 10 neon tetra and 4 dwarf Gourami to help with the cycling. Substrate polished rocks thoroughly rinsed; driftwood was boiled several times until no tannin discoloration; plants tied with fishing line and small amount of cyanoacrylate.The first 4 weeks were not an issue. We had ammonia spikes and then nitrate elevations which is why we did the frequent water changes; with additional solutions added to the buckets of water before adding into tank. We had no losses during the 4 week cycle; bacterial bloom in week 2. Only thing we change in the sump is filter sock (every 2-3 days) and filter sponges (weekly). I vacuum weekly so there is no rot under the stones.

View attachment 887969

Equipment:

• Unicliff 1058gph wave maker (Since the photo was taken we have repositioned the wave maker closer to surface and directed upward.)
• Jerepet 800gpm pump (set to about 60-70% of power because the return flow is not as fast)
• Fluval 32W 24inch LED light
• Hygger Fans (primarily to ventilate the hood and under cabinet)
• Hygger 500W water heater (though I'm not sure its been turning on because the house is warm and before we added it we were at a consistent 78F)
• Air bubbler that came with the tank (Replaced all the other devices as above)

We tested water with our aquarium store and was 0ppm for Ammonia, Nitrite, Nitrate so got go ahead to purchase and added after 4th week (they would not sell us anything before 4 weeks and our "starters" were purchased from Petco):

• 4 Angelfish
• 2 Leopard Cory Cats
• 1 Bamboo Shrimp
• 3 Balloon Rams
• 6 Otocinclus
• Plus the original 4 dwarf Gourami and 10 Blue Neon Tetra

We are currently starting week 9 and we have had some losses weeks 7&8.

1. 1 Cory cat found dead and unharmed in week 7; we had another nitrate/nitrite elevation so we increased water changes and added more bacteria solution
2. 3 Tetra (1 per day) in end of week 7; one of which I found in the mouth of Balloon Ram and then partially eaten in filter sock; another partially eaten in filter sock next day; one never found.
3. 1 Angelfish without injuries start of week 8. By this time we had controlled Ammonia and Nitrites to 0ppm; Nitrates 0-5ppm according to API color chart (using both test strips and solution kit).
4. Yesterday we came home in evening to find one of the Balloon Rams draped over the driftwood gasping. Transferred him to the 3G quarantine tank but he didn't survive long. This was the only one we saw sick before dying and he did not look sick earlier in the day.

All of the fish throughout this setup have been swimming, active, eating, pooping; no signs of distress until this Ram. His color faded, and that black mark under his eye was not there before. A few minutes after the photo he just went belly up. We did not have any medication.View attachment 887968

That’s a very interesting tank - don’t think I’ve seen one like it.

Sorry to hear about the losses but the ram may have died just because he was a ram. So far as I know, they were bred from Mikrogeophagus ramirezi and unlike the more robust Bolivian rams, those guys can be tough to keep alive even under ideal conditions. I’d not have chosen them for a new tank that had not finished cycling yet.

If the Angelfish are juveniles they should do ok but once they hit sexual maturity, around 10 months or so of age, they will probably start fighting and if two of them bond as a pair the 3rd may need to be rehomed. Might need to rehome two if they’re all males.

Are all the DGs (dwarf gouramis) male? if so, you may find they’re unwilling to share space with each other. They can be quite territorial, and the angelfish are very territorial when spawning. So are rams if they’re spawning, though they do stay low so with such a tall tank it might not be an issue - though if you have two male rams they may not get along.

Can you tell us numbered results for pH, GH, KH(alkalinity) and how high the ammonia or nitrite spikes were when you had them? It’s truly best to have your own test kits but the numbers of the results are what we need.

I would also be very curious to know the GH, KH and pH of the tap water as it comes from the tap, and what the pH is 24 hours later after a sample has sat out open for that time.

 

I'm not sure how to sex my fish. All the gourami look the same blue color and body shape, and they have so far gotten along. The rams are similar as well. The angels have different color variation of black and yellow; had 2 of each color variation. Looking online I think they're all female. They are supposedly less aggressive and not Koi hybrids so supposedly community friendly. I had no intention of breeding any of these; if it happens that would be cool.
I believe the rams are female as well; looking online there is no dorsal fin extension on any of them.

I had similar looking tetra, Gourami and angels in my very first tank. The rams, cory, and otocinclus are new to me.

I don't recall exactly but with the API 5-in-1 strips the GH is typically 180 and the KH I believe were in80s. PH is usually 7-7.5
Got home and tested the tank and everything is stable. pH 7.5, GH 180, KH 80. Using the solution kit Ammonia, Nitrite, Nitrate are 0

 

When you say changing filter sponges weekly are you throwing them out and getting new?? If so, I would recommend to stop doing that. Your sponges house most of the beneficial bacteria your tank has, so throwing that out is probably throwing your tank into a new cycle every week and will result in ammonia and nitrite spikes. You can clean them by swishing around/ squeezing in some of your tank water that you are removing for water changes. You should be seeing nitrate building up to indicate your tank is cycled (this is why you do water changes to lower nitrates). Ammonia and nitrite should always be zero in a cycled tank.

 

I'm not sure how to sex my fish. All the gourami look the same blue color and body shape, and they have so far gotten along.

Welcome to the forum. The dwarf gouramis are almost certainly all males. As indicated above, that is very likely to go bad as they get older.

 

It takes about 6 weeks to properly cycle a tank IF you have suitable filter media and substrate. Four weeks is not sufficient.

From the photo, it looks like the substrate has fairly large pebbles. Unlike fine gravel and sand such substrate provides limited surface area for the growth of beneficial bacteria and other microorganisms. Furthermore, by having a very tall tank with limited surface area, you do not have a lot of substrate.

You mention that you have an 8 gallon sump with a filter sock and sponges. How do you maintain that media? If you clean it too frequently or too thouroughly, you will be removing some of the beneficial microorganisms you are trying to develop. If you are replacing the media, that is even more drastic. That is why replaceable filter cartridges are not recommended by most experienced fishkeepers.

You are only 9 weeks into the setup; yet you are already up to what is probably full stocking level. When adding new fish after cycling a tank, you need to add them slowly starting with the least aggressive fish first. After only four weeks, you added quite a few additional fish.

When people purchase angelfish from a pet store, they are often around the size of a quarter or fifty-cent piece. They often do not realize that these cichlids are rather aggressive and they can grow to a size of a saucer (about 6 inches in diameter, not including the protruding fins). When fully, grown, they will need about 16-20 gallons of tank capacity per fish. Thus, your four angels would have maxed out the tank capacity. Since you already lost one, you should be OK for a while until they reach breeding age. Then one male and one female is all you will be able to maintain, assuming they are compatible. If not the dominant male may kill over competitors.

 

Hi TheBigT, just my opinion, it's not finished cycling, in a true cycling sense,. if it were you'd have nitrates building up every week, and once you have them, you'll never really get it totally to zero nitrates again without a 100% water change (which you really shouldn't be doing) or daily smaller water changes that allow it to keep between 0 and 5 ppm. it's what people would call "new tank syndrome" where the tank just isn't established enough to support all the occupants.

The tank is not "stable" or "established" yet. perhaps it's cycled, but it's not well established which is why you are experiencing the problems with the fish that you are. Corys will pick on algae and biofilm and supplement the scrap food that gets to them at the bottom if they get really hungry they will come up and feed with the other fish.

Rams are sensitive and so are the balloon rams, maybe even more so the ballon version over the regular rams.

Dwarf Gouramis have their problems also, some do well, some do not. Same goes for neons, there's just going to be losses with these fish.

I'd also think with the tank being a new set up, the Ottos likely won't do well either they are a "3-6 months in" kind of fish and need all the little stuff that builds over time to eat off of.

overall this is a lot of fish for a two month old new set up. it will only support the amount of life that it can and when you stock too quickly, the weaker fish will die off and the strong will survive, this is from small stress events that will occur through each day with the balancing act of the tank and the stocking level, it's generally a better to not add more than half of the current stocking level at any time for the fist 3-6 months as it all settles in and becomes established. there can be small spikes that you dont' catch on a test that stress them, there can be fish that are trying to adjust and settle in and can't get enough food. Just lots of reasons for the deaths to happen at this stage with the stocking level you have, and the species that you've chosen.

Your hardiest fish selection is the Angelfish and they can be difficult if exposed to stress events and not work well also. The tank selection is pretty ideal for angels, They can swim around and around and never hit a wall and it's got great depth for them.
I don't see anything necessarily wrong with your GH or KH, the pH is a little high for that species and the tetras but I don't think you need to do anything about that..I'm a angel fan, I don't see necessarily a problem with them, But maturity can throw you curve ball when hormones get cranking. I wouldn't replace the one that passed and just remain with the 3 of them, see how it goes.

I think the situation here is the tank just can't currently support the stocking and as a result you're losing the weaker fish either to predation for food, or to them not getting enough food and minor events wearing them down.Maybe less water changes, less cleaning except for the tank glass and let the nitrates build up to 20ppm before doing anything with a water change. let it all settle in, and get some biofilm and maybe even some algae on some surfaces whic te fish can graze on to tide them over.

The Bamboo Shrimp not being dead, and the fact its one of this or two of that, it's not a water quality issue, It MAY be a pathogen, but again it's rarely going to be something that affects so many species of fish and you don't see signs of disease on the dead or sick fish.
Parasite? Possible but doubtful also, but you can feed and check out their poop. see if anything is going on there.

My opinion, it's not a well established tank, and maybe they aren't all getting enough food and very little in the tank to forage on which is what's leading to the deaths after approx 4-5 weeks after purchase.

The cylindrical shape gives them an "infinity" swimming pattern if they want it, they can swim in one direction forever and could also be burning more calories doing it if that's happening. it's not like they have to turn in that tank and can just be swimming around and around. and not getting the behavior broken which happens in a rectangle or square.

then there's the 36" depth. it's not crazy deep, but there may be issues with the water at the lowest levels circulating up to the top and getting dead spots of low O2 down there at the bottom which fish will avoid while awake but may drift into when the sleep, and then theres a "sleep apnia effect" for the fish and a somewhat daily stress event where they struggle to breath while resting and drifting around.


Anyways Some ideas. I don't think it's an illness.off of what you observed and written, I dont' think it's water quality either. I can't imagine the sip would be fine while the larger creatures aren't ding as good.

I think it's just a combination of things, it being a new set up, the species chosen and their hardiness or ability to handle stress, and their ability to eat enough to sustain and thrive vs. their activity in the tank. .

I do think maybe upping the food, squeeze in a extra feeding or two each day (don't increase the amount of the feedings you do, instead you can toss in a pinch that they can eat in a minute every 2-4 hours and get them extra feedings like that when you pass to check on them). Easiest is just to add an extra feeding or two and see if it changes the dynamics and reduces any deaths, fighting, predation or stress, The additional food will leave some over for the shrimp and the cory and the ottos and help it all establish out to biofilm and establish microfauna like detritus worms and stuff for fish to forage on if they choose.
The dwarf gouramis are likely adults, but the other fish likely have growing to do and in order for that to happen they have to continually gain body mass, which translates to growth, and not burn more calories than they consume.which will restrict them and leave them "hangry".
in this respect, I think the feeding routine might be the issue and the weaker fish can't compete and end up dropping.

 

Hi TheBigT, just my opinion, it's not finished cycling, in a true cycling sense,. if it were you'd have nitrates building up every week, and once you have them, you'll never really get it totally to zero nitrates again without a 100% water change (which you really shouldn't be doing) or daily smaller water changes that allow it to keep between 0 and 5 ppm. it's what people would call "new tank syndrome" where the tank just isn't established enough to support all the occupants.

The tank is not "stable" or "established" yet. perhaps it's cycled, but it's not well established which is why you are experiencing the problems with the fish that you are. Corys will pick on algae and biofilm and supplement the scrap food that gets to them at the bottom if they get really hungry they will come up and feed with the other fish.

Rams are sensitive and so are the balloon rams, maybe even more so the ballon version over the regular rams.

Dwarf Gouramis have their problems also, some do well, some do not. Same goes for neons, there's just going to be losses with these fish.

I'd also think with the tank being a new set up, the Ottos likely won't do well either they are a "3-6 months in" kind of fish and need all the little stuff that builds over time to eat off of.

overall this is a lot of fish for a two month old new set up. it will only support the amount of life that it can and when you stock too quickly, the weaker fish will die off and the strong will survive, this is from small stress events that will occur through each day with the balancing act of the tank and the stocking level, it's generally a better to not add more than half of the current stocking level at any time for the fist 3-6 months as it all settles in and becomes established. there can be small spikes that you dont' catch on a test that stress them, there can be fish that are trying to adjust and settle in and can't get enough food. Just lots of reasons for the deaths to happen at this stage with the stocking level you have, and the species that you've chosen.

Your hardiest fish selection is the Angelfish and they can be difficult if exposed to stress events and not work well also. The tank selection is pretty ideal for angels, They can swim around and around and never hit a wall and it's got great depth for them.
I don't see anything necessarily wrong with your GH or KH, the pH is a little high for that species and the tetras but I don't think you need to do anything about that..I'm a angel fan, I don't see necessarily a problem with them, But maturity can throw you curve ball when hormones get cranking. I wouldn't replace the one that passed and just remain with the 3 of them, see how it goes.

I think the situation here is the tank just can't currently support the stocking and as a result you're losing the weaker fish either to predation for food, or to them not getting enough food and minor events wearing them down.Maybe less water changes, less cleaning except for the tank glass and let the nitrates build up to 20ppm before doing anything with a water change. let it all settle in, and get some biofilm and maybe even some algae on some surfaces whic te fish can graze on to tide them over.

The Bamboo Shrimp not being dead, and the fact its one of this or two of that, it's not a water quality issue, It MAY be a pathogen, but again it's rarely going to be something that affects so many species of fish and you don't see signs of disease on the dead or sick fish.
Parasite? Possible but doubtful also, but you can feed and check out their poop. see if anything is going on there.

My opinion, it's not a well established tank, and maybe they aren't all getting enough food and very little in the tank to forage on which is what's leading to the deaths after approx 4-5 weeks after purchase.

The cylindrical shape gives them an "infinity" swimming pattern if they want it, they can swim in one direction forever and could also be burning more calories doing it if that's happening. it's not like they have to turn in that tank and can just be swimming around and around. and not getting the behavior broken which happens in a rectangle or square.

then there's the 36" depth. it's not crazy deep, but there may be issues with the water at the lowest levels circulating up to the top and getting dead spots of low O2 down there at the bottom which fish will avoid while awake but may drift into when the sleep, and then theres a "sleep apnia effect" for the fish and a somewhat daily stress event where they struggle to breath while resting and drifting around.


Anyways Some ideas. I don't think it's an illness.off of what you observed and written, I dont' think it's water quality either. I can't imagine the sip would be fine while the larger creatures aren't ding as good.

I think it's just a combination of things, it being a new set up, the species chosen and their hardiness or ability to handle stress, and their ability to eat enough to sustain and thrive vs. their activity in the tank. .

I do think maybe upping the food, squeeze in a extra feeding or two each day (don't increase the amount of the feedings you do, instead you can toss in a pinch that they can eat in a minute every 2-4 hours and get them extra feedings like that when you pass to check on them). Easiest is just to add an extra feeding or two and see if it changes the dynamics and reduces any deaths, fighting, predation or stress, The additional food will leave some over for the shrimp and the cory and the ottos and help it all establish out to biofilm and establish microfauna like detritus worms and stuff for fish to forage on if they choose.
The dwarf gouramis are likely adults, but the other fish likely have growing to do and in order for that to happen they have to continually gain body mass, which translates to growth, and not burn more calories than they consume.which will restrict them and leave them "hangry".
in this respect, I think the feeding routine might be the issue and the weaker fish can't compete and end up dropping.

Thank you for insight. I admit I probably went aggressive but my first experience tank taught me wrong since it seems I got lucky nothing ever died in there.
We were done stocking the tank and don't plan on adding more unless we lose even more down the road.
The bubbler is the only thing I haven't replaced from original equipment and I'm going to be getting a new one with additional nozzles so I can add air stones in addition to the built in piping.
I'll up the feedings with large wafers and Tetra 5 day banquet tab.

It takes about 6 weeks to properly cycle a tank IF you have suitable filter media and substrate. Four weeks is not sufficient.

From the photo, it looks like the substrate has fairly large pebbles. Unlike fine gravel and sand such substrate provides limited surface area for the growth of beneficial bacteria and other microorganisms. Furthermore, by having a very tall tank with limited surface area, you do not have a lot of substrate.

You mention that you have an 8 gallon sump with a filter sock and sponges. How do you maintain that media? If you clean it too frequently or too thouroughly, you will be removing some of the beneficial microorganisms you are trying to develop. If you are replacing the media, that is even more drastic. That is why replaceable filter cartridges are not recommended by most experienced fishkeepers.

You are only 9 weeks into the setup; yet you are already up to what is probably full stocking level. When adding new fish after cycling a tank, you need to add them slowly starting with the least aggressive fish first. After only four weeks, you added quite a few additional fish.

When people purchase angelfish from a pet store, they are often around the size of a quarter or fifty-cent piece. They often do not realize that these cichlids are rather aggressive and they can grow to a size of a saucer (about 6 inches in diameter, not including the protruding fins). When fully, grown, they will need about 16-20 gallons of tank capacity per fish. Thus, your four angels would have maxed out the tank capacity. Since you already lost one, you should be OK for a while until they reach breeding age. Then one male and one female is all you will be able to maintain, assuming they are compatible. If not the dominant male may kill over competitors.

Thanks for your insight.
The sump doesn't get anything except replacement of the sock and filter sponge. I take some of my water change and soak the new sock and sponge in it. The bio bags have not been touched or even rearranged since I placed them. This photo is not from today. I can cut back on the sponge changes. But the socks don't seem to want to rinse out. And when they get backed up the water draining from the tank backs up and bubbles over the sump

 

Thank you for insight. I admit I probably went aggressive but my first experience tank taught me wrong since it seems I got lucky nothing ever died in there.
We were done stocking the tank and don't plan on adding more unless we lose even more down the road.
The bubbler is the only thing I haven't replaced from original equipment and I'm going to be getting a new one with additional nozzles so I can add air stones in addition to the built in piping.
I'll up the feedings with large wafers and Tetra 5 day banquet tab.

Thanks for your insight.
The sump doesn't get anything except replacement of the sock and filter sponge. I take some of my water change and soak the new sock and sponge in it. The bio bags have not been touched or even rearranged since I placed them. This photo is not from today. I can cut back on the sponge changes. But the socks don't seem to want to rinse out. And when they get backed up the water draining from the tank backs up and bubbles over the sumpView attachment 887999

Filter socks are very effective at taking out even the tiniest particles but, as you have noticed, they clog fast and it’s not so easy to rinse them well enough to use again. That will add up expenses.

Depending on how the sump media is arranged though, you may be able to replace the socks with Poret sponge - it’s the very best reticulated filter sponge available, very long lasting and easily rinsable and cleanable. You can choose from several pore sizes too, from 10 ppi (pores per square inch), 20, 30 and then 45ppi, which is super fine and will clog. Not all filter sponges are reticulated and those that are not don’t work nearly as well as reticulated sponge is - and Poret is the best of the reticulated sponges, having been made specifically for aquarium filter use. (No, I don’t work for the company , just my personal experience over years with assorted media).

But using some coarser sponge and putting a finer pore size as the last sponge that water passes through would give you good water polishing, which is what the socks are doing now, but without the need to replace socks and the sponges would easily last ten years or longer. Poret is very good stuff.

 

I'm not a sump person but your biological filter is the media that's submerged the blue "sponge" is a filter pad. The filter pad don't clean up well, but my point is neither the sock or the filter pad is critical for the biological filter they are meant to catch larger particles and remove them from the water column. The sock first then the pad for smaller stuff which keeps the pad from getting blocked up and particulate except for the finist stuff out of the biomedia.

As far as filter socks try a larger micron size, 200 micron just to catch larger particulates, use the pad for the smaller stuff and you can even use a 1 or 2 micron or 5 micron, underlayment under the filter pad for water polishing on occasion.

Generally people buy a couple polyester filter socks sized by the micron to each last in their tank about a week before being blocked up, rinse them well inside out and then machine wash them and air dry.

People are generally changing filter socks 1-2x a week to make sure they don't get blocked up and overflow and bypass it, and to remove the waste before it breaks down to nitrates, keeping 2 to 6 of them and washing out the dirty ones in a rotation and replacing them once they are wearing out with holes every 6-12 months.
Then the filter pad is catching from like 100-200 micron down to like 50 micron or 25 micron particulates. I just use the cheap white filter floss and just throw out my pad and replace. rarely is there anything there that blocks it up.

 

Hi TheBigT, just my opinion, it's not finished cycling, in a true cycling sense,. if it were you'd have nitrates building up every week, and once you have them, you'll never really get it totally to zero nitrates again without a 100% water change (which you really shouldn't be doing) or daily smaller water changes that allow it to keep between 0 and 5 ppm. it's what people would call "new tank syndrome" where the tank just isn't established enough to support all the occupants.

The tank is not "stable" or "established" yet. perhaps it's cycled, but it's not well established which is why you are experiencing the problems with the fish that you are. Corys will pick on algae and biofilm and supplement the scrap food that gets to them at the bottom if they get really hungry they will come up and feed with the other fish.

Rams are sensitive and so are the balloon rams, maybe even more so the ballon version over the regular rams.

Dwarf Gouramis have their problems also, some do well, some do not. Same goes for neons, there's just going to be losses with these fish.

I'd also think with the tank being a new set up, the Ottos likely won't do well either they are a "3-6 months in" kind of fish and need all the little stuff that builds over time to eat off of.

overall this is a lot of fish for a two month old new set up. it will only support the amount of life that it can and when you stock too quickly, the weaker fish will die off and the strong will survive, this is from small stress events that will occur through each day with the balancing act of the tank and the stocking level, it's generally a better to not add more than half of the current stocking level at any time for the fist 3-6 months as it all settles in and becomes established. there can be small spikes that you dont' catch on a test that stress them, there can be fish that are trying to adjust and settle in and can't get enough food. Just lots of reasons for the deaths to happen at this stage with the stocking level you have, and the species that you've chosen.

Your hardiest fish selection is the Angelfish and they can be difficult if exposed to stress events and not work well also. The tank selection is pretty ideal for angels, They can swim around and around and never hit a wall and it's got great depth for them.
I don't see anything necessarily wrong with your GH or KH, the pH is a little high for that species and the tetras but I don't think you need to do anything about that..I'm a angel fan, I don't see necessarily a problem with them, But maturity can throw you curve ball when hormones get cranking. I wouldn't replace the one that passed and just remain with the 3 of them, see how it goes.

I think the situation here is the tank just can't currently support the stocking and as a result you're losing the weaker fish either to predation for food, or to them not getting enough food and minor events wearing them down.Maybe less water changes, less cleaning except for the tank glass and let the nitrates build up to 20ppm before doing anything with a water change. let it all settle in, and get some biofilm and maybe even some algae on some surfaces whic te fish can graze on to tide them over.

The Bamboo Shrimp not being dead, and the fact its one of this or two of that, it's not a water quality issue, It MAY be a pathogen, but again it's rarely going to be something that affects so many species of fish and you don't see signs of disease on the dead or sick fish.
Parasite? Possible but doubtful also, but you can feed and check out their poop. see if anything is going on there.

My opinion, it's not a well established tank, and maybe they aren't all getting enough food and very little in the tank to forage on which is what's leading to the deaths after approx 4-5 weeks after purchase.

The cylindrical shape gives them an "infinity" swimming pattern if they want it, they can swim in one direction forever and could also be burning more calories doing it if that's happening. it's not like they have to turn in that tank and can just be swimming around and around. and not getting the behavior broken which happens in a rectangle or square.

then there's the 36" depth. it's not crazy deep, but there may be issues with the water at the lowest levels circulating up to the top and getting dead spots of low O2 down there at the bottom which fish will avoid while awake but may drift into when the sleep, and then theres a "sleep apnia effect" for the fish and a somewhat daily stress event where they struggle to breath while resting and drifting around.


Anyways Some ideas. I don't think it's an illness.off of what you observed and written, I dont' think it's water quality either. I can't imagine the sip would be fine while the larger creatures aren't ding as good.

I think it's just a combination of things, it being a new set up, the species chosen and their hardiness or ability to handle stress, and their ability to eat enough to sustain and thrive vs. their activity in the tank. .

I do think maybe upping the food, squeeze in a extra feeding or two each day (don't increase the amount of the feedings you do, instead you can toss in a pinch that they can eat in a minute every 2-4 hours and get them extra feedings like that when you pass to check on them). Easiest is just to add an extra feeding or two and see if it changes the dynamics and reduces any deaths, fighting, predation or stress, The additional food will leave some over for the shrimp and the cory and the ottos and help it all establish out to biofilm and establish microfauna like detritus worms and stuff for fish to forage on if they choose.
The dwarf gouramis are likely adults, but the other fish likely have growing to do and in order for that to happen they have to continually gain body mass, which translates to growth, and not burn more calories than they consume.which will restrict them and leave them "hangry".
in this respect, I think the feeding routine might be the issue and the weaker fish can't compete and end up dropping.

Still losing fish. Down to 6 Otocinclus, 1 Leopard Cory, 1 Bamboo Shrimp, 1 Angel, 4 Dwarf Gourami, 2 Balloon Rams, 6 Blue Neon Tetra.

I am feeding my fish 1 frozen brine tablet twice daily and they are all eating their fill; there is also a week long tetra food tablet which lasted about a week, and the Oto's are getting algae wafers too.

There is no sign of disease such as spots, discoloration, behavior changes; poop all looks the same and normal.
There is no sign of aggression between the fish, no one is chasing or pecking at anyone else. The larger fish as they die are untouched. The tetras well I can't find their bodies so I'm assuming through another forum that the Rams might be eating their bodies but unlikely capable of catching one to kill it. No such signs of being eaten on the angels when I pull them out.

Everyone keeps mentioning that the tank hasn't stabilized or finished cycling. But what is it I'm looking at? Early on it was explained that the bacteria load have to settle in so they can keep up with the food decay and plant/fish waste so that the toxic ammonia and nitrites can be controlled; and nitrates through water changes. In the last week I have performed no water changes, not even topped off any evaporation. I have not added any chemicals or solutions. I changed the water sock once since it was clogging and overflowing onto the filter sponge pads. Today after finding another angel dead, I vacuumed almost no debris from under the rock substrate, mostly just poop no food/rot. I put that water slowly back into the tank straining it through another filter sock (yes that was painful and crazy).
I've only drawn off by syringe 20mL from the tank and another 20mL from the sump twice daily for API kit testing and I have had 0ppm Ammonia, Nitrite, Nitrate. The dip strips are also showing 0ppm for each. If I did not have enough bacteria then shouldn't I have ammonia? Where is all the nitrite/nitrate if those have to be removed through water changes?

Our water is hard in Nevada, but I'm told by the Aquarium stores that they use city water and the fish are apparently acclimated? We have a water softener system in our house but not sure if that is tolerated by fish/plants
When we made our water changes before we use the outdoor bypass, filling buckets and adding API conditioner and stress solution to the water buckets while they sit to get up to room temp. We also used up 6 gallons of RO drinking water first with the API solutions.

 

Still losing fish. Down to 6 Otocinclus, 1 Leopard Cory, 1 Bamboo Shrimp, 1 Angel, 4 Dwarf Gourami, 2 Balloon Rams, 6 Blue Neon Tetra.

I am feeding my fish 1 frozen brine tablet twice daily and they are all eating their fill; there is also a week long tetra food tablet which lasted about a week, and the Oto's are getting algae wafers too.

There is no sign of disease such as spots, discoloration, behavior changes; poop all looks the same and normal.
There is no sign of aggression between the fish, no one is chasing or pecking at anyone else. The larger fish as they die are untouched. The tetras well I can't find their bodies so I'm assuming through another forum that the Rams might be eating their bodies but unlikely capable of catching one to kill it. No such signs of being eaten on the angels when I pull them out.

Everyone keeps mentioning that the tank hasn't stabilized or finished cycling. But what is it I'm looking at? Early on it was explained that the bacteria load have to settle in so they can keep up with the food decay and plant/fish waste so that the toxic ammonia and nitrites can be controlled; and nitrates through water changes. In the last week I have performed no water changes, not even topped off any evaporation. I have not added any chemicals or solutions. I changed the water sock once since it was clogging and overflowing onto the filter sponge pads. Today after finding another angel dead, I vacuumed almost no debris from under the rock substrate, mostly just poop no food/rot. I put that water slowly back into the tank straining it through another filter sock (yes that was painful and crazy).
I've only drawn off by syringe 20mL from the tank and another 20mL from the sump twice daily for API kit testing and I have had 0ppm Ammonia, Nitrite, Nitrate. The dip strips are also showing 0ppm for each. If I did not have enough bacteria then shouldn't I have ammonia? Where is all the nitrite/nitrate if those have to be removed through water changes?

Our water is hard in Nevada, but I'm told by the Aquarium stores that they use city water and the fish are apparently acclimated? We have a water softener system in our house but not sure if that is tolerated by fish/plants
When we made our water changes before we use the outdoor bypass, filling buckets and adding API conditioner and stress solution to the water buckets while they sit to get up to room temp. We also used up 6 gallons of RO drinking water first with the API solutions.

Have you seen an Oto latch onto the algae tab and actually consume it? They’re wild caught almost always and tend to refuse to eat anything except growing live algae. So they may not be eating and it’s quite common for them to die within the first few months after purchase, in part for this reason.

Softened water is not great for fish, though you can remineralize it to suit their needs if the softener uses salt it’s going to have more sodium in it than is good for most freshwater fish.

What exactly is a frozen brine ‘tablet’? It’s not a word I associate with frozen fish goods but I’m just curious about it.

You are correct that with all those fish there should be something showing up on the tests. The fish are producing ammonia and if it isn’t showing up as ammonia then it must have been converted but where are the nitrates that should be the end result.

I wonder if somehow this filtration system is actually DEnitrifying the nitrate, which would result in readings of zero, zero, zero and where denitrifiers are at work, the end result of the process is N, nitrogen gas, that goes into the air.

The odd bit is that denitrifiers are anaerobic only and do not function in the presence of oxygen, so where is denitrification happening, if it is in fact happening.

When aquarists talk about established tanks, what we’re talking about isn’t just being cycled. Aquaria are closed systems but there is plenty of life in them other than fish and among other things, the biofilm that grows on every surface that’s covered in water grows thicker with time and while I can’t tell you what specific effects that has, most shrimp keepers rely on heavy biofilm to feed their shrimp and many use supplemental bacteria to ensure the film is quite thick and a naturally grown biofilm takes many months to grow to what we think of as biological maturity.

It’s well known that some species fare poorly in tanks that are not biologically mature and you’ll read that it’s not advised to put them in tanks that have not been up and running without issues for at least six months.

 

Have you seen an Oto latch onto the algae tab and actually consume it? They’re wild caught almost always and tend to refuse to eat anything except growing live algae. So they may not be eating and it’s quite common for them to die within the first few months after purchase, in part for this reason.

Softened water is not great for fish, though you can remineralize it to suit their needs if the softener uses salt it’s going to have more sodium in it than is good for most freshwater fish.

What exactly is a frozen brine ‘tablet’? It’s not a word I associate with frozen fish goods but I’m just curious about it.

You are correct that with all those fish there should be something showing up on the tests. The fish are producing ammonia and if it isn’t showing up as ammonia then it must have been converted but where are the nitrates that should be the end result.

I wonder if somehow this filtration system is actually DEnitrifying the nitrate, which would result in readings of zero, zero, zero and where denitrifiers are at work, the end result of the process is N, nitrogen gas, that goes into the air.

The odd bit is that denitrifiers are anaerobic only and do not function in the presence of oxygen, so where is denitrification happening, if it is in fact happening.

When aquarists talk about established tanks, what we’re talking about isn’t just being cycled. Aquaria are closed systems but there is plenty of life in them other than fish and among other things, the biofilm that grows on every surface that’s covered in water grows thicker with time and while I can’t tell you what specific effects that has, most shrimp keepers rely on heavy biofilm to feed their shrimp and many use supplemental bacteria to ensure the film is quite thick and a naturally grown biofilm takes many months to grow to what we think of as biological maturity.

It’s well known that some species fare poorly in tanks that are not biologically mature and you’ll read that it’s not advised to put them in tanks that have not been up and running without issues for at least six months.

This is the brand of frozen brine shrimp I am feeding the fish. There is some fuzz and film on the driftwood that I see the shrimp going after; and I have seen it do similar on small patches of the large pebble substrate at the bottom. He has molted his shell one time around 1.5 weeks ago which I was told was a good sign(?).

These are the solutions I added in the beginning for bacteria Brightwell Bacteria, API QuickStart and stress coat.
This is solution I added in the beginning four weeks to help the bacteria Reeflowers Bacteria Feeder and Brightwell QuikCycl. Have not added those at all in the last 5 weeks.

The only thing I have been adding during water changes as I mentioned is the API condition and stress coat.

EDIT:
Yes I have seen the Otos eat the tablets; not as fast as the other fish go after the regular food but still.

Also to clarify... have not used any of the softened water.

And thank you for your input

 

This is the brand of frozen brine shrimp I am feeding the fish. There is some fuzz and film on the driftwood that I see the shrimp going after; and I have seen it do similar on small patches of the large pebble substrate at the bottom. He has molted his shell one time around 1.5 weeks ago which I was told was a good sign(?).

These are the solutions I added in the beginning for bacteria Brightwell Bacteria, API QuickStart and stress coat.
This is solution I added in the beginning four weeks to help the bacteria Reeflowers Bacteria Feeder and Brightwell QuikCycl. Have not added those at all in the last 5 weeks.

The only thing I have been adding during water changes as I mentioned is the API condition and stress coat.

EDIT:
Yes I have seen the Otos eat the tablets; not as fast as the other fish go after the regular food but still.

Stress Coat is a water conditioner, nothing more. The name is quite misleading but there is no point to using two water conditioners at once. Use one up, then use the other.

Ah I see about the brine shrimp. I think of those as cubes . It’s a good brand though, they supplement the shrimp, which few brands bother to do. Mind, I’d vary the diet some and not feed the very same food day in and day out. There are other frozen options. But if you only feed one cube, that’s not much for all those fish.

Bamboo shrimp are filter feeders. In a tank that big there should be enough small stuff in the water for one bamboo to eat but if it’s picking at surfaces it may be going hungry. It eats microscopic particles and critters that it catches in its fans and then wipes into its mouth.

Is there a current in that tank? Do you see the shrimp sitting on something with its fans spread out and just sitting there for hours, periodically wiping a fan across its face?

How long did you use that Reeflowers bacteria feed? That stuff strikes me as being a bit of a scam - it says it removes nitrate and phosphate and I do not know of any chemical that would do that, never mind bacteria that would survive in oxygenated water.

But I find it fascinating that the Brightwell Florinbacter you used says it contains anaerobic bacteria that perform denitrification. That is very interesting indeed given the lack of nitrates you’re experiencing, though where they’ve found a place to set up shop is puzzling to say the least.

 

Stress Coat is a water conditioner, nothing more. The name is quite misleading but there is no point to using two water conditioners at once. Use one up, then use the other.

Ah I see about the brine shrimp. I think of those as cubes . It’s a good brand though, they supplement the shrimp, which few brands bother to do. Mind, I’d vary the diet some and not feed the very same food day in and day out. There are other frozen options. But if you only feed one cube, that’s not much for all those fish.

Bamboo shrimp are filter feeders. In a tank that big there should be enough small stuff in the water for one bamboo to eat but if it’s picking at surfaces it may be going hungry. It eats microscopic particles and critters that it catches in its fans and then wipes into its mouth.

Is there a current in that tank? Do you see the shrimp sitting on something with its fans spread out and just sitting there for hours, periodically wiping a fan across its face?

How long did you use that Reeflowers bacteria feed? That stuff strikes me as being a bit of a scam - it says it removes nitrate and phosphate and I do not know of any chemical that would do that, never mind bacteria that would survive in oxygenated water.

But I find it fascinating that the Brightwell Florinbacter you used says it contains anaerobic bacteria that perform denitrification. That is very interesting indeed given the lack of nitrates you’re experiencing, though where they’ve found a place to set up shop is puzzling to say the least.

Sorry, I referred to the cubes as tabs because it's like a medication card where you punch one tab out. I was suggested to feed them extra because of the cylinder shape giving an "infinity swim" in someone's response earlier suggesting they might be burning too much energy... all the shrimp in the cube get eaten because I enjoy watching them, even the leopard cory has some. Andi also have the vacation feeding block that gets eaten over the week too.
I was told if I'm over feeding them it should cause ammonia or leave a lot in the cracks of the stone bottom. But my levels are 0 and vacuuming almost brings out nothing.

Yes the shrimp is often somewhere fans out filtering.

There is a wave maker that creates a flow current and of course the return from the sump. have bubble maker too. The reeflowers was last used a few weeks ago basically ran out around week 5or6, was probably using more than needed but was told the combinations would help accelerate establishing the Aquarium.