Planted Tank Guru
Join Date: Apr 2011
Location: Hamilton, Ontario, Canada
The problem with leaving the fish in, is that you are going to stir up all kinds of settles food and poop in the current gravel and you're trying to scoop it out, and if you drain out 80% of the water, that decaying food and poop is going to cause a huge ammonia spike, even more so because now your water is 80% less and therefore more concentrated. I would take out the fish, drain most of the water, take out the old gravel (and have fun, its fun to get every last piece of gravel out of a tank unless you take it and rinse it right out, etc, thats why my nice black eco-complete has small white and blue stones here and there). bucket the fish, put in an air stone, switch the gravel, fill slowly with water, run the filter for a while to clean out the cloudyness, then slowly put a fish or two back and see how they do first, then start to add the rest. Myself, I would even test the water after I put it back in first to make sure I didn't have a big spike
20g platy, , 2 x 10g shrimp, 3 x 20g shrimp, 7.5g shrimp and 1 great dane/mastiff puppy.
Sump Pimp #2
My Tanks and my shrimps