Okay, I'm back for more advice. I just got my planted aquarium started this week. I added Flouish as fertilizer and Flourish Excel for CO2 (I heard this was a good way for beginner planted aquariumist to start). I have two Nerite snails that I added fairly recently as well. The first day after I added the Flourish products, snails were fine. Second and third day, I was barely home, but when I was, I didn't see the snails. I read they have a tendency to hibernate sometimes, especially when adjusting to new tank environments. Today, I got a little worried when I still didnt see them. Did some research and saw conflicting accounts about using Excel with Nerites - some people say it's fine, others say it's harmful. Does anyone have insight on this? Also, I read some people dose daily with an eye dropper, but I simply followed the directions on the bottle and was planning to only dose after water changes. Also, I slightly underdosed, because I read how overdosing could be harmful to algae, which I want to keep around in moderation for the nerites to eat. Anyway, when I got home this evening the snails were out, but one looks really, really sluggish (no pun intended haha). I still did an almost 50% water change. I added more fertizilizer, but no more Excel just in case. I want to find out more about it in relation to snails before I use it again. For insight, tank plants are moss balls, dward hair grass, amazon swords and dwarf water lettuce.