Does vacuuming spike Nitrites?

[jaysono]

Well, last night I came home and did a good vacuuming of about 35% of the gravel towards the front of the tank and using an algae scraping sponge, I cleaned off the walls of my tank where this brown substance appeared to be growing.

As I approached and 'wiped' this brown stuff, it seemed to disenegrate like powder. Was this really algae? I was expecting more like a plant like substance. What does a bacteria colony look like, if it's even visible?

As I vacuumed my gravel I discovered something else!!! Well, I guess I now know why one Danio hoveres near the bottom of the tank and chases away all others. It appears in my dump water I counted at least 17 small (talking 2-3 millimeters) swimming things, which I assume are new Danio babies

With this vacuuming came a lot of buried debri and I ended up replacing about 20% of the water last night.

The good news : My Ammonia dropped from 1.0ppm where it's been the last few days to now somewhere between 0.25 - 0.50ppm, probably closer to the former. YEA!!!! Maybe I can finally get some new fish this weekend. (More on that in a second)

The bad/confusing news : My Nitrites went from 0 to 0.25 overnight. I'm assuming it's because I vacuumed up some good bacteria? Anyone else know why? Does vacuuming 30% of gravel really take out enough bacteria to result in a rise in Nitrites?

Now to my fish question: If I am lucky enough by Sunday to add some more fish, I was going to go with everyone's advice here and go for the Lamp Eye Tetra's. But how many should I introduce at a time. I know 6 is a schooling number, but I think 6 may prove harsh on the Bio-load. So maybe 2? 3?

 

[OrionGirl]

First and foremost--do not add any more fish until you have had ammonia and nitrite readings of 0 for at least one week.

The brown stuff sounds like diatom algae--very common in new tanks. Manual removal works, but the bloom usually fades out over time.

Cleaning the gravel does not remove bacteria. Have you previously had a nitrite spike? How old is the tank? If this is a fairly new tank, the nitrites spike is the result of the bacteria colonies developing enough to consume ammonia.

 

[jaysono]

Yes the Nitrite already had it's spike, and has recently dropped to 0.0 and had been holding there for a bit now. Only after my cleaning yesterday and the subsequent water reading this morning did it result in a a reading of 0.25ppm.

I plan in testing again when I get home today.

I thought I read on another post sometime back that thorough gravel cleaning can result in the death or removal of good bacteria, that why you should alternate vacuum sites on cleaning....that is not to vacuum all your gravel at one time.

 

[JSchmidt]

If you have only an undergravel filter or if you have other filtration that is just barely sufficient, I think vacuuming the gravel could cause problems, because the thin layer of gravel on top that holds the bacteria would get buried. This would reduce it's effectiveness. If you have sufficient biofiltration occuring elsewhere (e.g., in an HOB or canister filter), I don't think cleaning the gravel should lead to any problems. If you stir up a bunch of crud and don't remove it from the tank (with the water change) that could cause problems, too.

If vacuuming the gravel leads to an ammonia or nitrite spike, I'd question whether your bioload was close to exceeding your filtration capacity.

Jim

 

[jaysono]

No, I don't think I was close to exceeding it. I have a 16 gallon tank with a Penguin 125 Bio-wheel filter. I only have 4 danio's in my tank, and am at feedings about once a day (if that).

In addittion to the vacuuming, in which I agree I may have buried some good bacteria, I also cleaned the little diatom algae spots about the tanks walls. When I went to clean them, they more or less turned to 'dust' if you will. Perhaps the disentgration of this diatom algae (since none really came off on my sponge) may have thrown off the reading?

 

[TPIRman]

If you still have measurable levels of ammonia in the tank, you haven't experienced the true ntirite spike yet. The ammonia should drop to zero soon, and then you will be dealing with nitrites for a while. You will need to wait this out and, as OG said, wait another week with ammonia and nitrites both at zero, before considering more fish for the tank. You're still in the middle of the nitrogen cycle -- it can be frustrating!

Keep up a good regimen of water changes so that the level of toxins remains low. Water changes will not slow your cycle down. And don't be afraid to vacuum your gravel. That was not the cause of your nitrite spike -- the nitrification bacteria multiplying and converting the excess ammonia to nitrite was the cause. This is why you witnessed a drop in ammonia at the same time the nitrites went up. Vacuuming the gravel is far better than the alternative, so keep it up.