Bacterial bloom after 2 years of healthy cycle?

[Purplewiseman]

I’m not so new to this hobby, I have had a 30 gallon running for a little over 2 years with no major issues. My water parameters including nitrate and nitrite, PH, hardness etc. have been stable. A couple weeks ago i made a mistake adding water to my tank and accidentally stirred up a lot of filth into the water which triggered a bacterial bloom making my water murky. I’ve researched as much as I can find on ways to fix it. I’ve cut back on feeding even fasting for a couple days, changed my carbon in my filter, tried a less powerful light, done my weekly water changes. It seems like nothing is helping. It is not hurting the fish or parameters in any way it is just unsightly. If anybody has had this issue before please tell me how you fixed it. Forgive me if I’m not using the forum properly I’m new to the whole forum thing. Thank you for reading

 

[Byron]

That is quite heavy. Can you please give the numbers for all tests you can do...ammonia, nitrite, nitrate, pH; and what is the GH (of the source water is fine for this)?

Bacterial blooms in established tanks are caused by specific issues involving organics. Nitrate and pH are key in this aspect. There is also a greenish tint here, suggesting an algae bloom; this too is due to dissolved organics on which unicellular algae in the water will feed.

How frequent are water changes, and what volume? Is the filter kept thoroughly clean? Is the substrate well vacuumed during water changes? Over stocking and/or over-feeding contribute as well.

 

[Purplewiseman]

That is quite heavy. Can you please give the numbers for all tests you can do...ammonia, nitrite, nitrate, pH; and what is the GH (of the source water is fine for this)?

Bacterial blooms in established tanks are caused by specific issues involving organics. Nitrate and pH are key in this aspect. There is also a greenish tint here, suggesting an algae bloom; this too is due to dissolved organics on which unicellular algae in the water will feed.

How frequent are water changes, and what volume? Is the filter kept thoroughly clean? Is the substrate well vacuumed during water changes? Over stocking and/or over-feeding contribute as well.

Hi byron thank you for your reply, my nitrate is between 0 and 20 ppm, nitrite is between 0 and 0.5 ppm, ph is 6.5 which is intentional because all of my fish prefer low ph and has been consistent for a while now, GH is between 0 and 30 ppm. As for the green tinge that is from the light I have on at the moment, it would appear more white-ish with a normal light. I clean my filter frequently, I did have a problem with over feeding in the weeks prior to the issue but I cut back since then and have been thoroughly cleaning my substrate and doing weekly 20% water changes. My tank is not overstocked with fish by any means but I do have an abundance of mystery snails (12+ about an inch - 1.5 inches). I will of course stay open minded to it being an algae bloom but if im correct a large water change will help with an algae bloom but have no effect on a bacteria bloom? As im writing this I just did about a 45% water change.

 

[Byron]

OK, no much in the way of issues there. But you should increase the volume of the weekly water changes, 50-60% would help (stay with this volume too), Keep the organics out (filter cleaning, substrate, minimal feeding). You probably stirred things up and it will settle. Water changes sometimes help, sometimes not with blooms, because the organics are still there, though dissolved organics in the water obviously may lessen.

Make sure nitrite is zero, always.

 

[Purplewiseman]

OK, no much in the way of issues there. But you should increase the volume of the weekly water changes, 50-60% would help (stay with this volume too), Keep the organics out (filter cleaning, substrate, minimal feeding). You probably stirred things up and it will settle. Water changes sometimes help, sometimes not with blooms, because the organics are still there, though dissolved organics in the water obviously may lessen.

Make sure nitrite is zero, always.

Thank you for the advice, I will up the weekly water changes, stay on top of organic material and cut feeding down to a minimum. I’ll stick to this routine for a couple weeks and see if it helps. Most people I ask tell me to use material clumpers like clear fast but in my experience they do more harm than good.

 

[DoubleDutch]

I think it is possibly algaebloom instead of bacterial bloom

 

[xxBarneyxx]

Is the filter kept thoroughly clean?

Seeing as you have had a tank running for over 2 years I probably don't need to clarify. Just in case though.

When cleaning the filter do it in water taken from the tank, NOT tap water. You do not want to kill the bacteria off in your filter media.

Sorry this is probably explaining something you already know but I have seen people do it before

But yeah agree with Byron here. The previous overfeeding and stirring up all the organics from the substrate are most likely the cause and it will sort itself out.

You didn't mention ammonia in your tests, is this something you have tested for?

I suspect the combo of overfeeding and disturbing the substrate has caused a bit of a mini cycle. This is why Nitrite is not zero and you have had an algae/bacteria bloom.

As above regular water changes and vacuuming any organics out of the tank will help (by keeping Nitrites down and reducing organics). I would expect it to last maybe a week or two.

 

[Byron]

Most people I ask tell me to use material clumpers like clear fast but in my experience they do more harm than good.

I assume this refers to so-called water clarifiers. Never use these in a tank with fish present. Most clear the water by causing the microscopic particulate matter to stick together so the larger matter is more easily/readily caught in the filter media (especially the sponge/foam/floss media). Problem is, these substances also cause the gills of the fish to stick together. Chemical solutions are never the answer, just nature itself. If the biological system is balanced and left alone with no additives, things will usually function well.

When cleaning the filter do it in water taken from the tank, NOT tap water. You do not want to kill the bacteria off in your filter media.

This is actually not the case. In a new tank without live plants, it is probably advisable to use old tank water to rinse the filter media, out of an abundance of caution and if it makes the aquarist feel better. But in a tank with live plants, or one that is established (a few months), this is not necessary. The reason is that first there will be nitrifying bacteria elsewhere, especially in the substrate; second, the chlorine in the tap water is not going to kill off all the bacteria anyway, unless the level of chlorine is really excessive--as I noted earlier, the nitrifying bacteria in a new tank comes from the chlorinated tap water to begin with, so obviously the chlorine is not going to kill all of it, if it even kills any of it. Third, with plants there is no need for biological filtration anyway as the plants will take up the ammonia/ammonium (unless things are way out of whack) and that is as far as it gets.

I have been rinsing filter media under the tap for 30+ years, and I have never had ammonia or nitrite above zero in any of my tanks. Nitrate is in the 0 to 5 ppm range, which may be closer to zero for4 all I know.