I'm cycling a new 29H bowfront with 3 leopard danios and 2 cories. This is day 9 and the ammonia is at .50 but nitrites are still 0. I've read it's best not to do water change before the cycle is complete but my instinct tells me to do a water change to dilute the ammonia so it won't stress the fish. Which is correct? Thanks for your help.
Your instinct is correct. The bacteria will settle on the substrate and mostly in the filter media. Go ahead and change out some water. I'd do a big one today, and another tomorrow, and daily if needed to keep the levels down.
This group has been awesome in answering questions. You will need to do water changes necessary to keep ammonia and nitrites below .25 which may mean doing 2 in one day.
Good luck!!
ok here is what i have to say about not doing water changes during cycling, you need to do water changes.
1. Bacteria lives on surfaces, the gravel, the ornaments, the glass and most of all the filter media, taking out water will not take out the bacteria
2. No matter how much water you take out the fish will poop so there will always be enough ammonia to cycle a tank
3. I'm not sure that this is correct but no matter what level of ammonia, bacteria multiplies at the same speed.
I had this tank for weeks and never saw a nitrite.
Then I talked to some people here and a good friend of mine here. This friend kinda recommended me to do a "do-over" by doing three consecutive 50% water changes. Back to back. I needed to do this because I panicked and started throwing ammo lock and all kinds of crap in my tank.
I did it. Drained half the tank, filled it. Drained it again, filled it. Drained it again, filled it. I needed to do that to "start over" without completely draining my tank. 8 Days later, I got my nitrites. Now, in that 8 days, I probably did 5 more 50% water changes AFTER the "do-over". Now...I'm STILL doing it because I have nitrites now. I'm in day 11.
Also, don't clean your filters. Leave them alone. If you do clean them down the road, do it with water from your tank.
If you've been throwing ANYTHING in your tank that isn't Prime, do what I did. It works.
