I haven't bought it yet but I am considering it, just wondering what the capacity is. I would be keeping tropicals in there, just small things like: neons, glass cat fish and my two mystery fish (see my other questions about them lol) and I would like to buy more neons (I have 6) and more glass catfish (I have two, though I'm looking at my SpyOrb as we speak and I appear to have lost them...they are hiding!). That is my answer