I'm pretty experienced with aquariums, but have never tried this before. I am running RO
water on two new aquariums and setting them up one at a time. So I'm starting from scratch with no cycling done.
A friend of mine has an established 20 gallon, so yesterday we put my Bio-Wheel filter on his tank. I'm going to leave it there for a bit to "borrow" his bacteria.
Question: How long does my filter need to run on his tank to get a good colony going?