thanks for your response rrkss. the tank in question is an eclipse corner 5 with built-in penguin mini filter. i don't think i have enough room in the tank (or the adjoining electrical outlet.. i've already got a full surge strip running with my other tank and that)for an additional sponge filter (they require an air pump, right?)... and besides, i'm worried about worst case scenarios... (i.e. i buy new fish needing to be quarantined and come home to find a surprise outbreak of some sort in the established tank i would be using to seed the sponge).
so it seems like fishless cycling would be a better bet for me. i did have the tank cycled, as i upgraded it to the current maintank i have now, and i have been throwing a bit of flake food in there to "feed" my bacteria every so often while it is empty, but i'm not sure if that has worked to maintain the cycle (and i haven't tested parameters lately), but i'd like to get on a regular ammonia-dosing schedule to make sure the tank is ready for the next sick fish or new friend.
perhaps i'm just being bad at math, but i have no idea how to translate teaspoons or milliliters of ammonia into parts per million... is there some kind of formula based on the percentage content of ammonia? and if not, is it possible to overdose? how do i avoid that?
thanks in advance. =)