Actually, I use PFS and there's just as much area for bacteria as normal gravel. As for filter cleaning, I have a 55G with PFS and do my normal filter cleaning with no ill effects. So I wouldn't say not to do proper filter cleaning all at one time, I do and I have a very heavy bioload and everything is fine. Bacteria is everywhere, gravel, filter, plants, ornaments, etc. A mature tank won't see any mini-cycle because of doing proper filter maintenance, even with pool filter sand.