Any idea why my fish are dying?

Hello, I have a 30-gallon aquarium with 12 guppies, 3 glofish, 3 mollies, 1 balloon molly, and 1 glowlight tetra. I do 50% water changes every 2-3 weeks. Ever since I started in the aquarium hobby, I have been having trouble keeping fish alive. Currently, whenever I buy either dwarf gouramis, mollies/balloon mollies, or guppies, they usually die within 2-3 weeks. My only conclusion is that they are dying from stress but I can't figure out why. The only fish that usually stay alive are my glofish and glowlight tetras. At first, I thought that they just had a bacterial infection so I bought aquarium salt, Melafix, and Metroplex and dosed them in a 10-gallon quarantine tank. It didn't work. My local pet store told me that maybe my Nitrate levels were too high so I got a live plant. It didn't work and the plant melted and died. I thought maybe my hang on the back filter wasn't big enough so I bought a Fluval 107 canister filter. It still didn't work. The entire time I also had an ammonia test kit but whenever I tested my water it would always say zero. Does anyone have any suggestions?

Water parameters:
Ammonia - 0ppm
Nitrite - 0ppm
Nitrate - between 0 and 20ppm
Chlorine - 0ppm
pH - 8.4ppm
KH - 300ppm
GH - 0ppm
Temperature - 78°F

 

Seems like the water is coming through a softener. Do you have access to unsoftened water?

 

No, but I do plan to get Seachem equilibrium which should boost up my gh. Do you think that would solve my problem?

 

It's not ideal, but apart from that, needs more water changes and perhaps feed less. 50% water change once a week would be better.

 

It's not ideal, but apart from that, needs more water changes and perhaps feed less. 50% water change once a week would be better.

Ok but I don't see how that would affect anything since my ammonia and nitrite levels stay at zero and my nitrates are always between 0 and 20ppm. I also only give them one pinch of food once or twice daily.

 

Ok but I don't see how that would affect anything since my ammonia and nitrite levels stay at zero and my nitrates are always between 0 and 20ppm. I also only give them one pinch of food once or twice daily.

Ammonia is not the only thing affecting water quality so overfeeding still needs to be avoided

I would get the source water sorted out first. Mollies and guppies need minerals and higher pH and gournamis prefer softer lower pH water

 

If ammonia and nitrite aren't the only things affecting water quality then what else does? Are you saying that 1 pinch is too much for 20 small fish?
I don't mean to argue I'm just a little confused, that's all.

 

If ammonia and nitrite aren't the only things affecting water quality then what else does? Are you saying that 1 pinch is too much for 20 small fish?
I don't mean to argue I'm just a little confused, that's all.

When poop breaks down it dissolves into organic molecules which reduces water quality. These dissolved organic carbon are not easy to measure without lab equipment Generally, high levels of DOC correlates with reduced health and lifespan.

These molecules have complex interactions with organisms, some are fuel for pathogenic, non-beneficial bacterial growth such as weird growth on fish that we often see

Overall, my opinion is just dont feed too much and dont leave too much waste in the tank and you wont have to worry about DOC

 

Alright, I see. I'll start changing my water weekly. Also, would you recommend that I put aquarium salt in my tank or should I avoid it until I see problems occurring with my fish?

 

No, don't add salt there is no need

 

Ok, thanks for the advice.

 

I find this case confusing.

Your water has very high PH and KH but 0 GH. Is it well water?

What is buffering the water if its not calcium or magnesium?

Have to think your livebearer fish are dieing because of the water where as tetras being naturally softer water fish are coping better.

Try the equilibrium.

 

I normally put aquarium salt in my tank. I tested my water with and without the salt and it seems to make the ph and kh higher. Without it, my ph is neutral and my kh is near zero. I get my water from a water station and I haul it back home.

 

Ahhh I see.

Your water is basically like RO or somthing then. Neutral PH with very little of anything in it i'd guess?

Salt will remineralize water partly so that explains it. I'm still surprised by that PH and KH though!

You would be better suited choosing fish that like super soft water or even Blackwater conditions. Rainforest species.

Or you could try to buffer it naturally with crushed coral in your filter. Marine sand substrate would do it too!

 

What types of fish would you reccomend?

 

Tetras. Up your glow light school number. You could add a second school like neons or cardinals.

Dwarf cichlids such as apistogramma could be cool.

Sure there's lots of soft water fish out there from rasboras and pencil fish species too. The 30 gallon limits a bit or you could do some of the larger cichlids.

 

Would I be able to mix dwarf cichlids with guppies and tetras?

 

Do you have access to tap water? The water from the water station seems to be either softened water or distilled/RO water. If it is distilled water then you can use a general purpose re-mineralizer that adds GH and KH. Aquarium salt is NOT a general purpose re-mineralizer which was probably why you were having issues keeping fish.

If you have to haul water from the water station everytime for a water change then I would try a difference approach to fishkeeping....water change every week would be way too much work. A lowly stocked planted tank that you only need to top off with distilled water is probably the easiest way

 

Tap water is the only water I use for my aquarium. It would cost me 3 times as much water to use RO. Doing water changes every week shouldn't be a problem since our water station is only 15 minutes away and the water there is cheap. I don't haul my water every time I do water changes, it's only when our cistern gets low. I'm pretty sure I can get equilibrium and crushed coral from my local pet store so I can pick some up tomorrow. I can also pick up some live plants as well. What type of plants would you recommend?

Basically what I've got from this is to not put in aquarium salt, start changing my water weekly, boost up my GH and KH with a mineralizer, and get some live plants.

 

Tap water is the only water I use for my aquarium. It would cost me 3 times as much water to use RO. Doing water changes every week shouldn't be a problem since our water station is only 15 minutes away and the water there is cheap. I don't haul my water every time I do water changes, it's only when our cistern gets low. I'm pretty sure I can get equilibrium and crushed coral from my local pet store so I can pick some up tomorrow. I can also pick up some live plants as well. What type of plants would you recommend?

Basically what I've got from this is to not put in aquarium salt, start changing my water weekly, boost up my GH and KH with a mineralizer, and get some live plants.

Hmm I see. So Equilibrium only adds GH, you still need to add KH. I know Nilocg and Salty Shrimp have GH + KH remineralizers. Not a fan of Seachem as they love to split their products up so you have buy like 3 products to achieve one thing

Crush coral will help with both GH and KH as well. But need to plan out which route you are going to take. The calculation for how much remineralizer to add is based on the softness of your water, and crushed coral will slowly leech GH and KH which will mess with the calculations.

Easy plants are rotala rotundifolia, hygrophila corymbosa, anubias

 

Maybe what I might do is put crushed coral in my aquarium substrate or with my filter media and then have a remineralizer on hand just in case my GH and KH get too low. Would that sound like a decent plan?

 

Parameters were:

Water parameters:
Ammonia - 0ppm
Nitrite - 0ppm
Nitrate - between 0 and 20ppm
Chlorine - 0ppm
pH - 8.4ppm
KH - 300ppm
GH - 0ppm
Temperature - 78°F

Was this the tap water or the water from the water station? I'm a bit confused.
If KH is 300ppm, it's like 16-17 dKH. You don't need any more carbonates. That's enough for a saltwater coral tank and then some.
You likely need to bring pH down some, and you need to raise GH.

I mean ideally you'd need a pH above 6.8 but not into the 8s., kH and GH above 4 and that's stable for most all species of fish. And it's basically gravy from there.

I think testing of the source water, whether tap or station water, and then determining which one need the least amendment in order to be stable and viable would be the right solution. After that just finding the right dosage of amenders.
Aquarium salt isn't it. That's mostly sodium and some calcium or magnesium. It's OK but likely not what you needed. Adding Epsom salt (magnesium sulfide) and straight calcium, like powdered egg shells. Or other less "sodium" or "chloride" sources would be better than adding salts.

 

Parameters were:


Was this the tap water or the water from the water station? I'm a bit confused.
If KH is 300ppm, it's like 16-17 dKH. You don't need any more carbonates. That's enough for a saltwater coral tank and then some.
You likely need to bring pH down some, and you need to raise GH.

I mean ideally you'd need a pH above 6.8 but not into the 8s., kH and GH above 4 and that's stable for most all species of fish. And it's basically gravy from there.

I think testing of the source water, whether tap or station water, and then determining which one need the least amendment in order to be stable and viable would be the right solution. After that just finding the right dosage of amenders.
Aquarium salt isn't it. That's mostly sodium and some calcium or magnesium. It's OK but likely not what you needed. Adding Epsom salt (magnesium sulfide) and straight calcium, like powdered egg shells. Or other less "sodium" or "chloride" sources would be better than adding salts.

My tap water is the water from the water station. The parameters for my tap water by itself are:
pH: 7
KH: 0ppm
GH: 0ppm

Also, since I had previously added aquarium salt, my ph has gone way too high. In the past, I was told by my local pet store that my fish were probably dying from a bacterial infection and only aquarium salt would fix it. Today I went in and asked how they harden their water. Apparently, they get theirs from a source where it is naturally hardened. I have bought some Equilibrium (It's the only thing they had) to boost up my GH and some Tetra Correct pH to hopefully bring down the pH for now.

As of my last water change, I have not added any aquarium salt and I won't be adding any more into my main tank. I do have a 10 gal quarantine aquarium which I can use for the aquarium salt If I ever have problems with bacterial or fungal infections. I would consider using Epsom salt and powdered eggshells to boost the GH but the powered eggshells also raise the ph which I don't want.

Hopefully, this clarifies everything for you.

 

Maybe what I might do is put crushed coral in my aquarium substrate or with my filter media and then have a remineralizer on hand just in case my GH and KH get too low. Would that sound like a decent plan?

Crushed coral is fine. What fish are still alive in the tank? Guppies and mollies prefer harder water with high pH. Glowlight tetras can tolerate hard water but they are naturally softwater fish.

 

I have guppies, mollies glofish and glowlight tetras.

 

If you really have water that is neutral pH and has GH = 0 and KH = 0, then unfortunately your water is unstable and will be deadly to fish. But can easily be fixed.

Your water has apparently been treated and is pure.

What is happening is that water has nothing dissolved in it. This makes the pH unstable.

When you add some salt it is causing the pH and KH readings to be high You see it as high pH and high KH.

At very high pH the water is lethal because any trace amount of ammonia is deadly. You may not be seeing the ammonia on the test, but even trace amounts below what you can measure are toxic at unstable high pH.

The solution is to get your water fish ready.

May I suggest a KH=5 and GH=5 as a starting point for healthy fish water.

The economical way to do this is to use Baking Soda to raise KH and sea salt to raise GH.

If you want to do it more properly, you can get a pre-mixed powder like this one and follow the directions:
sera GH/KH-plus | sera


Since you are starting with pure water, you will need to get used to re-mineralizing your water with these powders. You can just put the correct amount of powder into the last bucket you use to change the water.

You have great water for keeping any kind of fish you like. You are very Lucky!!


Also find some sea shell, or oyster shell and put them in your tank. Anything with some hardness that will help you keep your water healthy. Limestone rock is good. But any shell or coral from the sea is great.

 

I have some good news! So after dosing my tank yesterday with some Seachem Equilibrium, my fish started showing some positive results. For example, earlier one of my guppies was upside down at the top of the tank. Today she is upright and is able to swim around. Her swimming isn't perfect yet, she's a bit wobbly, but there's some improvement!

 

Excellent. This will stabilize your water. You can use Equilibrium (for GH), and a bit of baking soda (to set your KH) which will stabilize your water. Then you can get used to how much of each to add to your water change water to keep things consistent. Shoot for GH=KH=5. This is still soft water so will not shock your tank, but will make it stable and not have dangerous pH swings.

You need good aeration as well to get stabilized.

 

You need good aeration as well to get stabilized.

I have an aerator with a bubble wall so that shouldn't be a problem.