What ever you do, don't add an apple/mystery snail! They will pollute the tank like you wouldn't believe. I added a 1.5" snail (Pomacea bridgesii) to my 10g, about a week ago just to see if they will eat my algae. In just a week, my nitrate reading went from 5mg/L to 15+mg/L! At first, I couldn't figure out the cause of nitrate spike. It couldn't be the snail, it's too small to cause that much increase in nitrate....or so I thought. I, then see my snail, happily munching away at the algae, while leaving a massive trail of excrement behind him. The snail is producing more waste than all my fish put togather! Looks like I'll have to double the water changes.
