I mini-cycled my 37 tall when I threw 4 Panda Cory's in it. Figuring they were a shoaling species, I wanted to add 4 at once, and then 2 later on. Small ammonia and nitrite spike was the result (approx. .50 PPM on both). I had a local breeder give me 10 angelfish shortly afterwards that were around nickle-sized and I figured since I was already doing daily water changes to let the filter catch up, I may as well ignorantly pile on the bio-load. I was just growing them out to keep a pair out of the group when they were closer to half-dollars.
Needless to say, I was changing water every day for just over 3 weeks. Nobody showed any signs of distress or anything, except me, because daily water changes are a drag.
I also recently added 4 Otto's to that tank, and 4 small female fancy tail guppies to my 55 to correct the m/f ratios. Both mini-cycled around .25 - .50PPM of ammonia and nitrites, and were back to 0 after one day of very light feeding and one day of no feeding at all with a 30% water change each day. The Otto's and guppies were pretty small though.
Do I recommend it? I can't say either way to be honest. I've never had a problem with a crashed cycle that a daily water change couldn't fix, but that's my own personal experience and I don't feel comfortable telling someone else to follow in my footsteps if there's risks involved. Just because I didn't have any problems doesn't mean someone else wont.
