Aeration- how hard is it to over do it

So I "over" built my first 20 gallon. Fish are for the kids designing and trouble shooting are for me. I got equipment to slightly over stock a 60 gallon which is my actual goal but for training purposes I got a 20. If I upgrade I have the stuff already- I hate buying twice.

I got a fountain pump to pump up from sump so on and so on. Guppies (petsmart) all died- still trouble shooting why. They were all gasping at the top which is a symptom of.... everything. It did get me thinking about o2 and co2.

So how hard is it to over aerate? A while ago I had so much there were micro bubbles in the tank coming through the hose from the sump. I moved the bubbler further away and it faded but there were alot. So how hard is it to get lethal amounts of dissolved gasses in the water?

 

What are the water parameters of the tank? pH, temp, ammonia, nitrite, nitrate?

And are you pumping CO2 in? I don't think you need to worry about over aerating with room air

 

The most common reason for gasping is to little oxygen in the water, or something in the water such as ammonia or nitrite. Is the tank fully cycled yet? If you could fill out the tank info in your profile, it helps us diagnose things a bit better. In your profile, click the "About Me" section and you can fill in the specifics. Just make sure you click save after each entry. If you haven't read about the Nitrogen Cycle its must read info for fishkeeping. Clicking the word should link to the page explaining it.

 

Well I didn't include mine just cause I'm curious how hard it is to over aerate- not just mine but in general. No co2 just room air through a bubbler. All levels are 0 with nitrates showing a slightly dehydrated color of urine but not quite 5ppm on the apI scale. Temp- which effects gasses is at 80.5- can't get it to go lower aiming for 78 still tinkering with that.As for the gasping I have that narrowed down to petsmart stock, a ph spike (which didn't effect the rcs) or parasites that came with the fish.As for cycling I'm drawing a partial blank on it's completness. I have another thread about that. Not many nitrates showing but some, ammonia a clear 0 but I forgot nitrites so I assumed I botched the cycling.After the test arrived next day I tested old water I saved in vials all came back .25ppm which should not have killed the guppies. New water a clear blue of 0 so time will tell. So I struck nitrites from the list. Since the trumpet snails (which are a terrible guage since nothing kills them ) and the rcs who were just added were fine I'm looking at the fish specifically in regards to their untimely demise. Had 5 and they died at a rate of about 2 per day. When I had 3 left I noticed the gasping and ph spike 7.8 up to 8.2. Did a water change 30% next day 1 more died got home from work 1 more died as I did a 90% replaced the play sand with #20 pool filter sand and put remaining guppy in temp tank with some salt thinking nitrites. She died next day- I also moved a bubbler up from sump to try and oxygenate the water. One had fungal growth second to last day around mouth, which is a symptom of other stuff so I'm head scratching the die off. All toxins are inside of habitable parameters though.

The most common reason for gasping is to little oxygen in the water, or something in the water such as ammonia or nitrite. Is the tank fully cycled yet? If you could fill out the tank info in your profile, it helps us diagnose things a bit better. In your profile, click the "About Me" section and you can fill in the specifics. Just make sure you click save after each entry. If you haven't read about the Nitrogen Cycle its must read info for fishkeeping. Clicking the word should link to the page explaining it.

Will work to include parameters when I know they are more stable. Since I'm still questioning the cycle status.

 

Any amount of Nitrite is extremely toxic, far more toxic than ammonia. While fish can tolerate some amount of ammonia for short periods of time, even .25 of nitrite can kill fish very fast. Nitrites are also the worst part of the cycle, as they suddenly spike through the roof, and take seemingly forever to finally go down and zero out. In the nitrite stage of a cycle its especially helpful to do large daily water changes to keep them low as if they get too high theyll stall a cycle.

 

I Get mixed information on the toxicity of nitrites at .25 but what it did was get me scratching my head on how hard it is to over aerate. Just as an idle curiosity.
Personally I'd like to be able to defenitivley say it was nitrite so I can trouble shoot from there which is keep a close eye and wait for what will now be a super slow cycle.

 

Any amount of Ammonia or Nitrite is toxic. Ammonia is more tolerable to fish compared to Nitrite, but should always ideally be 0 in a cycled tank. Nitrites are MUCH more toxic than ammonia, and should also always be 0. If you didnt have a nitrite test kit, and you were cycling with fish in, they were very likely subjected to extremely high nitrites at some point, which could cause irreversible damage. During a cycle, Nitrites often spike up off the charts initially. I know when testing the water in my 55 gallon while it was cycling, at one point I had to dilute the tank water 50/50 with tap water just to get Nitrites to a readable color.

Regarding your PH swings, PH will often change after 24 hours or so once it comes out of the tap. What happens is, water in the distribution system is pressurized, and thus contains gasses. Once it comes out of the tap, the pressure is released, and these gasses start to rise and remove themselves from the water, which in turn can make the PH change (usually up). If you find that your Fresh tested tap has a drastically lower PH than what's in your tank, it may be that the water hasnt had a chance to settle and stabilize. If you haven't yet, try testing some tap water that's been sitting out for 24 hours. Even better if you can run a bubble or airstone in the container to help really get those gasses out. This will give you a better idea of what your actual PH is. You may find it easier depending on the difference in PH numbers, to get a water storage container of some sort, even a bucket would work, and fill it up the day before you do water changes. That way, the PH is settled to its true value once its time top use it, and eliminates the possibility of PH shock. If the numbers aren't too far off, and you're doing say 20-30% changes, it shouldnt alter it enough to have any ill effects. Say your tank is 7.8, your tap is 8.2, a 20% water change should only bring it up by 0.1 which is negligible, and it should go from 7.9 to 7.8 within an hour or so.

Sorry to jibber jabber on and on, just trying to give you as much info as I can think of to help.

 

Sounds weird, but you'd better got a 60G as training for a 20G.
Bigger tanks are more easily to balance and ecen to maintain (sounds weird again). But think the nitrogyn-cycle is more important than the oxygin one in this case. Only thing with over-aeration you'll get less CO2 for the plants to grow. Fish will love you for the high oxygin-level that won't be higher than in the air above the water though.

 

Any amount of Ammonia or Nitrite is toxic. Ammonia is more tolerable to fish compared to Nitrite, but should always ideally be 0 in a cycled tank. Nitrites are MUCH more toxic than ammonia, and should also always be 0. If you didnt have a nitrite test kit, and you were cycling with fish in, they were very likely subjected to extremely high nitrites at some point, which could cause irreversible damage. During a cycle, Nitrites often spike up off the charts initially. I know when testing the water in my 55 gallon while it was cycling, at one point I had to dilute the tank water 50/50 with tap water just to get Nitrites to a readable color.

Regarding your PH swings, PH will often change after 24 hours or so once it comes out of the tap. What happens is, water in the distribution system is pressurized, and thus contains gasses. Once it comes out of the tap, the pressure is released, and these gasses start to rise and remove themselves from the water, which in turn can make the PH change (usually up). If you find that your Fresh tested tap has a drastically lower PH than what's in your tank, it may be that the water hasnt had a chance to settle and stabilize. If you haven't yet, try testing some tap water that's been sitting out for 24 hours. Even better if you can run a bubble or airstone in the container to help really get those gasses out. This will give you a better idea of what your actual PH is. You may find it easier depending on the difference in PH numbers, to get a water storage container of some sort, even a bucket would work, and fill it up the day before you do water changes. That way, the PH is settled to its true value once its time top use it, and eliminates the possibility of PH shock. If the numbers aren't too far off, and you're doing say 20-30% changes, it shouldnt alter it enough to have any ill effects. Say your tank is 7.8, your tap is 8.2, a 20% water change should only bring it up by 0.1 which is negligible, and it should go from 7.9 to 7.8 within an hour or so.

Sorry to jibber jabber on and on, just trying to give you as much info as I can think of to help.

Not so sound rude but I grasp these concepts, don't completly agree, and am trying to drive the conversation into my original question about aeration. Nitrites would have been .25- all probability is that was the height of the spike. As for toxicity not debating if they are toxic but how toxic and at what level .25 being very low and the fish being guppies I do not think it was sufficient for suffocation and organ failure. Possible? Yes. From a trouble shooting stand point I lean more toward other possibilities before I revisit nitrites.

Ph spike was during day time.

Sounds weird, but you'd better got a 60G as training for a 20G.
Bigger tanks are more easily to balance and ecen to maintain (sounds weird again). But think the nitrogyn-cycle is more important than the oxygin one in this case. Only thing with over-aeration you'll get less CO2 for the plants to grow. Fish will love you for the high oxygin-level that won't be higher than in the air above the water though.

It's more a mechanical experiment and to make a 20 gal tank have 30 gal of water. I realize that more water is easier to balance, it's not easier to keep on a second floor of a home, cheaper, or easier to move when the army says "hey your going here next year pack up."

Plus I like the challenge. I'll get 60 eventually just not now.

On aeration- let me he more specific how much air do I need to push into water and at what rate to be as risk of gas bubble disease?

Also since normal air has both co2 and o2 if I dissolve normal air (o2 dissolves easier) won't I keep a constant rate of both co2 and o2? At lower volumes of course.

 

I'm sorry, didn't mean to sound condescending. Just trying to help trouble shoot. Regarding aeration, extra aeration shouldn't cause any harm to fish, if anything the oxygen rich water is beneficial to them.

My comments regarding nitrites were sort of shooting from the hip, as I don't know how your tank was cycled. If it was cycled fish in, no matter how much filtration you have, you still likely had a point where nitrites were at least 1.0ppm for a short period.

 

No problem I enjoy forums but I'm quickly learning it is not like it was in the 90's. So I tend to... come off too firm. It's a generalized approach, that I should probably consider catering to individuals instead of one size fits all.

Cycling since it was at .25 I'm thinking it was not as cycled as I thought but the tests we're everyday and if cycled those nitrites would now be nitrates or still present and since nitrates are low I'm leaning toward uncycle due to my over site and low nitrites.

There are 30 gallons of water and only really 5 fish with a notable bioload for 4 days. With a combined biomass of maybe an ounce.

Unless... OK say ammonia is 1ppm the bacteria convert it. Since matter can neither be converted or destroyed that 1ppm went somewhere. Right? Some became nitrites but 1ml of ammonia won't turn to 1ml of nitrites since some would go to the biomass of bacteria. So accounting for bioconversion maybe .75ml turns to nitrites then same again .5 to nitrates? Not precise but conceptually sound.

Nitrates start at like 5ppm on the test don't they?

 

I believe 1.0ppm of ammonia converts to 2.7ppm of nitrite and then lastly 3.2ppm of nitrate. hampalong can verify the exact ratios.

Also Jsigmo works in a water treatment plant, so a lot of this stuff is right up his alley.

Nitrates do start at 5.0 on the API test.

 

Really so... it goes up? Then yeah my nitrates should be up there especially since they accumulate

 

Yep. This is also why Nitrites are such a pain when cycling, as when converted it's that much more for bacteria to have to process, and the nitrite phase of the cycle is often the most dreaded. It's slow, and when they spike up over 5.0 ppm they start to really stall the cycle which is common more so in Fishless cycling. Fish in cycling, depending on stock and bioload, you can expect to see 0.5ppm and up. Guppies, and livebearers in general are heavy waste producers for their size. However having a 20 gallon tank with an effective 30 gallon of water works heavily in your favor.

As far as CO2, with aeration, it should stabilize around 5.0 ppm, which is safe, and normal. I'm not familiar with gas bubble disease, I'll have to read up on that.

 

I just found it yesterday when I did my "besides nitrites what could suffocate my fish" research. Basically water can become saturated where gasses bubble out examples of this are carbonated beverages and the bends at depth when diving. Now I question the because of a few factors- not to say the disease is fake but to question the probability that it will happen.
1. Gas saturation is difficult to achieve in agitating water. Both the bends and carbonated beverages are caused by pressure change. High pressure dissolves it low pressure releases gasses.
2. High surface area reduces dissolved gasses as does agitation when saturated. Saying that water not at capacity will dissolve what's in the air and saturated water will dissipate it.

So main concern is that my pump is waaaaayy over what I need. Since I'm still learning basics of fluid mechanics I went over the top with my pump trying to account for verticle water push. I had to split the intake in two with over half my water pressure returning to the sump. (Fountain pump not aquarium pump)
Something to the tune of 220gph. Drilled tank with 1/2 overflow at about 90gph. That with my over the top bubbler system (trying to grow algae in sump) capable of over saturating the water being the bit that got me thinking. I think probably safe but made me wonder.

I have a lot of filtering going on lol

 

I don't think you need to worry about oversaturating your water. However, the flow is likely too much for your small tank.

 

Flow to the tank is about 90gph which would be 4.5 rotations an hour (ish) the heavy flow goes back to the sump and never effects fish. It is also not going back through the filter... thought that might be too much flow for bacteria, though I'd prefer it go back through the filter.

Edit: plants gently sway and there are points where I saw fish go chill out towards front of tank.

 

Sorry about that, didn't see your actual numbers. 90 GPH in a 20 gal is a little low actually. You should aI'm for 8-10x GPH through the filter for the tank size (so 160-200 GPH for your tank). Someone please correct me if I'm thinking about this wrong...

 

No your about right but I was concerned about more flow. My thoughts are that the sump accounts for the additional need. I have two 1/2 overflows and I have it where the second received a slow drip and the first is running at about capacity. Since the second is a backup I am hesitant to have it actively drain since a complete clog in one would spell disaster for the tank.

 

A canister full of media rates at x10 per hour actually delivers about x5-6 per hour, so a sump pump delivering 5-6x is about the same.

I've glossed over this thread. It appears to me that you're refusing to accept that your problems are happening because the filter isn't cycled. No offence but you seem to keep dismissing it in favour of your own approach. Cycle the tank properly and I don't think you would have needed this thread.

 

Read it again then. As well as the title. The thread is a question on air bubbles not my tank cycling. My refusal is an attempt to keep the thread on the topic I posted about- but thanks for the condescending feed back have a good day.

 

Read it again then. As well as the title. The thread is a question on air bubbles not my tank cycling. My refusal is an attempt to keep the thread on the topic I posted about- but thanks for the condescending feed back have a good day.

Just my opinion. I apologise if it sounds condescending.

 

I love a good debate and discussion but what's frustrating me is I have spent this entire thread explaining my tank. Admitted that it probably is not cycled but not convinced that nitrites are my culprit all the while trying to say that my question was spawned by these issues not by something I want to fix in my build as I do not think I am over oxygenating my personal aquarium but seeking to discuss this principal. Perhaps I'm in the wrong subform but it seemed the best fit via what I saw on mobile.

The strong reaction is not personal as I know your trying to help. Sorry if it came off against you personally as this is the second time I've made this apology in the same thread to two people. Lol

 

As long as you are in an open system, you cannot oversaturate the water with any of the gases. More aeration (airstones, etc.) will just keep the water well stirred, and keep things closer to equilibrium with the surrounding air, but cannot force more gas to dissolve than the saturation point (for that temperature and pressure ).

In fact, the extra stirring and exposure of the water to the ambient atmosphere will allow it to lose gasses just as well as absorb them. It just speeds up the transfer either way.

So, fear not the gas over saturation theory.

The bends happens because a diver moves too quickly from a higher pressure situation to a lower pressure situation.

As you pointed out, water can hold more gas in solution when under higher pressure than when under lower pressure. At the deeper depth (higher pressure) higher concentrations of gasses end up dissolved in a diver's blood. If he then ascends (moves to a lower pressure environment ) faster than this dissolved gas can come out of solution in a controlled way, the gas will come out of solution anyhow, forming bubbles, just like when you open a bottle of soda, and the dissolved CO2 suddenly comes out of solution.

You probably knew all of that. But just remember that because you are not pressurizing the fish and their surrounding water, then suddenly releasing that pressure, they cannot suffer from anything like the bends, if that makes sense.



Something else killed the fish.

In my experience, you cannot have too much aeration.

The gasping behavior can be a symptom of a lot of different things.

 

Are there aquarium systems that create these circumstances? I have not seen any but people report the disease. Maybe industrial aquariums?

 

Sounds like the OP has "dad got a new toy and can tinker with it, only thing is there's fish messing it up" syndrome.
That's how I started years ago, I got the fish for the kids, all the mechanical and stuff was my thing, DIY heaven.

 

Yup exactly. Original idea involved small aquaponic system, but since I was a kid I liked terrariums. Plus the nitrogen cycle is nearly identical to composting. So the process is familiar. I like problem-solving stuff so I built the stand, plumbing, filter and sump. Then after all this 5 fish kia got me trouble shooting and a whole new set of data to analyze. If I could get a picture to upload I'd show you monstrosity

 

Are there aquarium systems that create these circumstances? I have not seen any but people report the disease. Maybe industrial aquariums?

The way I understand it, you can have this problem if you subject the aquarium to a sudden increase in temperature such that some of the dissolved gasses present in the formerly cold water have to come out of solution, so they form gas bubbles everywhere, including inside of the fish.

There are also some ways of introducing saturated water that is under pressure into the aquarium such that this water ends up supersaturated in its suddenly lower pressure state in the aquarium.

But generally, circulation and aeration actually protect from all of this by assuring good gas transfer so the water maintains equilibrium with the atmosphere, and is well mixed at all times.

Sudden temperature changes are bad for a number of reasons.

Leaks in pumps or pump piping (presumably on the inlet side) can allow air to enter and be forced into the water. Pump cavitation caused by this can whip that air into the water, and possibly cause supersaturation.

So you probably should make sure your fountain pump setup isn't cavitating.

Do not restrict the inlet side of the pump, and don't let it suck in air bubbles. You want the volute to be fluid packed and unrestricted at all times. Then, introduce the water coming from the pump into the aquarium by letting it spray onto the surface of the aquarium, rather than through a tube below the surface, or worst of all, near the bottom.

 

Hmm mine goes into about 2/3 of the way down (8in down maybe a little less) and was in fact sucking air bubbles in from the sump. I try to aerate in the sump then pump in to make it quiter.
Yesterday I moved the bubblers away and the suspended air bubbles decreased in the tank but it still has a few larger bubbles either from the siphon break hole or pump I am not sure.

Interesting