Alisa

Hi, we are starting a new tank - 85 liters tropical fresh water. We set it up (no life plants currently, as thought it would be easier for beginners), let it run for a week adding "Stability" (which is supposed to reduce if not illiminated new tank syndrom). After a week let in 4 Zebras Danios (2 days ago). Two of them were smaller than the other 2 but all seemed to be fine. The following day fed them - all food eaten by all of them, all very active, althought 2 big ones seemed to chase smaller ones. After the 2nd night - two smaller fish are dead
The water parameters have been the same all this time: ammonia 0, Nitrites 0.3-0.5, Nitrates no more than 10. pH 7.2 Water temperature 26C
After taking dead fish out, i did a small water change (maybe I shouldn've, but reading different articles, got to coclusion, that better to change than not to change and good bacteria is attahched to hard surfices?)
I am not sure now, what to do - zebras danios should be kept in groups of about 6, so will 2 of them be ok for the time being? Or should we get another couple while the water is still at the beginning of the cycle?
One of the fish is behaving a bit strange - seems to be swimming fast up and down the back corner and along the back wall after being fed. They all did it now and again, but this one is has been doing it quite for a while now, occationally distracted by the other fish.
Appriciate any advise. Thanks.

AggieYen

This is why we tend to advise people to do a fishless cycle, so you don't have to worry about fish dying off while the cycle establishes itself. Any nitrites present will be poisonous to the fish that you have in there, so as long as you are reading nitrites, do partial water change, but don't vacuum the gravel to minimize disturbance to the bacteria cultures.

Your cycle has begun, but it hasn't finished, because you're still reading nitrites. When both ammonia and nitrites are down to 0, and nitrates are under 10 (if they're above 10, do another partial water change to bring that down), then you're good to add fish in, just be careful not to add too many fish at a time.

My catfish did that quite a lot as well, swimming fast up and down the back corner of the tank... never did figure out why it did that. He was perfectly healthy, but sometimes he would do that for an hour.. used to make me dizzy!

Alisa

Thanks, but that is what is confusing - I thought, once the fish is in, ammonium is supposed to go up first and then, when it drops, nitrites to go up. How could it start cycling without ammonium rising?

AggieYen

NitrAtes are the end product of the cycle, so going by the fact that you have nitrates, I'd say your tank has started cycling. Unless of course, your water from the tap has nitrates in it, in which case that's a different story altogether.

Because you still have nitrItes, i'd say your cycle isn't completed, because at the end of the cycle, the bacteria would have converted your nitrItes to nitrAtes. Again, unless your tap water already has nitrites in it. I'd say, do a test on your tap water and see what the readings are.

My guess your ammonias has gone up unnoticed, if there are nitrites - you may have missed an ammonia spike?

Narcicius

Aggie has got you covered, I assent to everything she just said.

Alisa

Thanks, the guy in the aquarium shop said ammonia was not rising because of the "Stability" creating enough bacteria to break down ammonia. Will monitor nitrites and nitrates. Got 2 more Zebras Danios - all 4 now swimming together fine.

AggieYen

I'd take what he's said with a pinch of salt - the only product folk around here recommend that actually helps cycle a tank is Biospira. I haven't used Stabilitiy, so I won't comment on the product itself, but I will say to monitor your ammonia, especially, extremely carefully. More fish die from ammonia poisoning than anything else in new tanks.

Narcicius

Is using products like Prime a good idea to remove ammonia in an emergency?

COBettaCouple

I'd recommend Prime as the tap water conditioner for ANY tank, but especially a tank that is cycling.

Narcicius

What about if your tank is established and an ammonia spike come outta nowhere, I know it can and does convert ammonia into bacteria food, but is it a good idea to use in an emergency to save some fish.

COBettaCouple

That's one reason why I like to use it for our main water conditioner - in case of any unexpected spikes or mini-cycles.

Narcicius

Thank you because I am currently using it regularly to keep some misplaced fish alive in an uncycled tank, I thought this might poison the fish if I put Prime in the water too much. Keep in mind I only do it with water changes and use only correct dosage, and I don't know of anything else that would keep my fish alive. So any advice other than Prime, btw its working great I just get a little scared putting chems in the tank like that.

COBettaCouple

I got a dropper bottle for dispensing Prime since we fill gallon jugs with water to add to the tanks. 1 drop per gallon is enough, but 2 drops doesn't cause any problems.

Narcicius

Will the adding of prime slow the cycling down at all, I mean it keeps the ammonia down so is seems like the bacteria might develop slowly in the tank, slowing the whold cycling process down, and I'm sorry if I completely hijacked this thread.

COBettaCouple

Prime doesn't so much lower the toxins as locking them. I'm not a chemist, but I think the basic idea of how Prime works is that it bonds to the nitrogen toxins and neutralizes them as far as the fish go.

We fishless-cycled a 30g tank in 3 weeks with all the water being treated with Prime so it doesn't do anything to slow the cycle.