How long is the nitrite spike?

HI guys and gals.

Am cycling with fish (again, not planned but we had an emergency) about 2 weeks ago. I used a cycling product (bacteria) called Tetra SafeStart before putting the fish in. I had a huuuge ammonia spike pretty quickly, and with regular water changes that soon tailed off to zero (in the last 2 days). My nitrites have been very high in the last 3 or 4 days (> 5!), and so are my nitrates (> 100!). I don't even know how these fish are surviving this. I change the water at least 2x a day now, until the nitrite is down to 0.5, and it only takes a few hours to creep up again.

My question is: how long are the nitrites going to go on shooting up like that? If the answer is a long time, I need to quit my day job and become a professional water changer.

 

Unfortunately it could be done today or it could be done 2 weeks from today, it's different for everyone. One thing you can do is slow down the feedings. The nitrite is the waste product of the good bacteria that is eating the ammonia. So if there is a lot of ammonia (food, waste from fish, etc.) then there will be an equal amount of nitrite until the good bacteria that eat that and produce nitrate have a chance to grow (by the way, they grow slower then the ammonia converting bacteria). So if you lessen (not remove completely of course) the amount of food being fed, then there won't be as much waste from the fish, which means less ammonia, which means less nitrite, which means less nitrate ;D And if you are using that bottle Prime that you finally was able to receive, then that's why they are living through this . Works pretty well doesn't it. If you aren't then man those are hardy fish.

 

Wow, thank goodness for Prime! Yes, that is the bottle that I found so hard to get.

OK, I'll try to reduce the feedings although it's already a quite minimal. I actually thought there was a dead fish in there because of such high levels. But that's impossible, or he'd have had to jump from another tank (not one of mine, even), and crawl in my tank to die!

Shall I vacuum the gravel? I used to have the 3 plecos in there and man could they poop. I know it's not a good idea when you cycle, but something's got to be done. It got to a point when the 3 plecos were in there when I thought 'sod it, I'll vacuum anyway'. So I did, a bit, because they were poo'ing layer upon layer. It was horrid. I didn't really disturb the gravel then, though, just the LAYER of poop hovering above the substrate. Maybe I should actually vaccuum/shake the gravel in four different go's (4x 1/4 of the aquarium, so bacteria at least stands some chance of settling).

 

Ah this was the pleco tank.... ok then that would explain those levels. Don't worry about under feeding then as once all that waste is removed the levels won't be spiking so high. Yes in this case it would be advisable to vacuum out the gravel. Do just like you said, do 1/4 of the tank, give it a few days and do another 1/4, etc. Keep up with the 2 times a day water changes though as this is the critical part of the cycle (I did the same and I only had max nitrite readings of 2ppm and was using Prime the entire time). Once you get some of that waste out of the gravel you won't have such movement of the levels. Also it's possible that the tank will cycle before you even get done cleaning all the gravel.

 

OK, that sounds good. Thanks for confirming.

The bit I don't get is my nitrates in a smaller tank (10G) with all 3 plecos + all the mollies (back when I didn't know about overcrowding...) were nowhere near as bad. It's like the remembered they were plecos once they were on their own.

I miss the small one. :'( I really hope the pet store does what he says and refuses to sell them to people with a small tank, or I could have definitely given him a better home than that.