I haven't had any problems with fry getting sucked up through the pantyhose. Wool cant hurt either, or a sponge. But, the pantyhose are easy and they do work.
pH and water hardness are not the same thing. water hardness is the amount of dissolved mineral content in the water, measured by gH and kH (mostly gH for these purposes). I ask because getting more "difficult" cichlids to breed usually requires you to at least get the general water hardness right. South American cichlids like the apistos like soft water, africans like hard water. The fish can be adapted to live in different conditions sometimes, but often won't do as well, or be happy enough to breed. I have had varying success keeping apisto/ram species in harder water. Some adapt and live fine ,but don't breed; and others have wasted away.
