The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.
Hello everyone. I was wondering if after I do a fish-less cycle and before I do a 90% water change if I could take out my substrate and add in a new one?
You can, it might cause a hiccup in the cycle but it's not usually a big deal. If it is really a concern though you could do the swap and then dose/test for a few more days to be sure.