Liz, I don't know how, but I managed to read "plants" instead of sponge. I wouldn't bother with the seltzer water for a sponge, it's more of a live plant thing! I've used H2O2 to kill the stuff otherwise.
I've been pointing a few people your way for the pitch black rams, seems like there's a rumble about them now at least. If these apistos of mine don't pan out I might get some rams from you. Non-composted ones, I mean. :D