Bacterial bloom- two months in

[AnotherHumanPerson]

About two months ago, I did a deep-cleaning of my 29 gallon’s substrate, removing a substantial amount of mulm. A few days later, the tank water became milky. After testing the water, it came out with high PH, Hardness, and buffer with zero ammonia, nitrate, and 20 nitrite. I assumed that it was just stirred up substrate, so I did a 50% water change. It got worse. After some googling, I came upon the conclusion that it was a bacterial bloom, and that it would solve itself in a few weeks. It didn’t. About a month ago, I purchased a school of celebes rainbowfish for the tank. I didn’t think that that they would be affected. They all died in a week. Afterwards, The cloudiness was so thick I couldn’t see the plants in the back. Now, here I am. The cloudiness has gone down a bit, and now there is a biofilm on pretty much every surface. Are there any anti-bacterial meds I can dose that can fix this, or should I just “nuke” the tank? I am too emotionally exhausted from this whole experience to do anything that needs more effort.

Edited September 17, 2022 by AnotherHumanPerson

[rockfisher]

I think the problem probably started with the deep clean. What I think happened was an imbalance in Beneficial bacteria be the bad bacteria. When you cleaned you removed the good bacteria and bad took off. There is all kinds of both bacteria in the tank. Any time you do anything major to the tank it’s a risk. Do you have anything alive in the tank still? 
 

@Guppysnail @Ken Burke  @Fish Folk   @Colu

Edited September 17, 2022 by rockfisher

[AnotherHumanPerson]

Pest snails, assassins, and plants are the only thing still alive. 

[Guppysnail]

It sounds like a serious bacterial bloom to me. Possibly from stirring nutrients possibly a parameter swing that knocked out some beneficial bacteria. Heavy bacterial blooms consume oxygen like crazy. My understanding is bacteria consume more oxygen than fish. This could have directly harmed the rainbows or caused enough stress some preexisting factor became opportunistic and took them down. 
 

@modified lung???

[Ken Burke]

Define “deep cleaning”.  I’ve taken tank down, rinsed the gravel thoroughly, and restarted the tank without an bacterial bloom, so I wouldn’t start assigning causality to your deep cleaning right off.  It sounds like a bacteria bloom, but that could be from several things.  
 

There are several commercial products that have beneficial bacteria.  You might try cleaning the tank (to make sure nothing died in a back corner) and adding something like fritzZyme.  You probably already realized adding fish right now is not the best idea.  Baby it along until the nitrites are back to 0.0.  If the water hasn’t cleared up by then you may need to think through a few other things like filtration or lighting.  

 

[KittenFishMom]

When my tank went cloudy I had an HOB, a large sponge filter and and air stone in the HOB. Anyone of them would have been rated for up to 20 gallons, and I only had 10. I always have extra air stones. That may have helped my cloudiness clear up faster as the bacteria could break things down faster.  The corys, neon tetras and the betta are all fine. I haven't seen to 2 yoyo loach from the big box store in a day or 2, but they might be hiding. I gave up on seeing them after a few days, and then one evening they were swimming all over the tank. There are plants and hollow places for them to hide. I was sure they were dead and eaten when they appeared out of no where last time. I don't think I could net them if I wanted to without taking everything out of the tank. 

[AnotherHumanPerson]

On 9/16/2022 at 7:58 PM, Ken Burke said:

Define “deep cleaning”.  I’ve taken tank down, rinsed the gravel thoroughly, and restarted the tank without an bacterial bloom, so I wouldn’t start assigning causality to your deep cleaning right off.  It sounds like a bacteria bloom, but that could be from several things.  
 

There are several commercial products that have beneficial bacteria.  You might try cleaning the tank (to make sure nothing died in a back corner) and adding something like fritzZyme.  You probably already realized adding fish right now is not the best idea.  Baby it along until the nitrites are back to 0.0.  If the water hasn’t cleared up by then you may need to think through a few other things like filtration or lighting.  

 

I gravel vacced pretty much the whole tank which, at worse, had up to an inch or so of mulm. I wouldn’t be supprised of some beneficial bacteria was living in there.

[Guppysnail]

On 9/17/2022 at 10:01 AM, AnotherHumanPerson said:

I gravel vacced pretty much the whole tank which, at worse, had up to an inch or so of mulm. I wouldn’t be supprised of some beneficial bacteria was living in there.

My bare bottom snail hatch/fry tanks seldom ever get vacuumed unless the mulm is 1/2 in deep and I have no fry at the time. When I do I always get bacterial blooms. I add an extra airstone and that seems to help it sort itself out faster.