Small (tiny) Tank Beginner

Question
Hi! There seems to be a dearth of information on the internet about my particular question, so I figured I should ask an expert! My family keeps larger saltwater tanks (150+ gallons) at home, and I love caring for the fish, but I've left for college, and after my first semester realized that I miss watching them swim. I think saltwater is too complicated and expensive to do on a small scale (dorm room size), so I figured I'd switch to freshwater. The largest I can reasonably accommodate is a 2.5 gallon tank, 2 being preferable. I'd rather not get a betta, but some of the smaller, more active fish. I'd love to keep zebra danios or tetras, but I'm concerned for keeping less than 6, as they are schooling fish. Is it acceptable to keep 6 small danios in this size tank? or is there another species/combination of 2-3 fish that would be better? Also, do you recommend plants or not? I won't have a filter, but will do weekly maintenance (which is still less demanding than the salt tanks at home!).  Moving the fish in between semesters is not an issue, as I have a friend who will keep them for me, so they don't have to endure the trip home. Thank you so much!

Answer
Hi Jimmy,

Unfortunately, 2 gallons is too cramped for active fish. By definition, active fish need lots of room to swim about! It is also not enough water to dilute the wastes of a group of schooling fish. Even if you go by the "inch of fish per gallon" rule of thumb (which has its flaws) this tank is way too small for anything but a 2" fish. The smallest tank zebra danios can be kept in is a tank 24" wide, such as a 15 gallon long. Don't be fooled by those "glofish kits" which are tanks about this size, with a black light so that you can watch the fish in the dark...this is just a marketing gimmick! It's an entirely inappropriate home for danios. It's a fine home for raising fry or keeping some freshwater shrimp - that's about it, unless you start looking at specialized fish such as microrasboras (you can Google that for more info) or least killifish.  

One thing that could work for you is Petco's bookshelf tank:
http://reviews.petco.com/3554/14978/reviews.htm
At $50, it's pricey for such a small setup, but the dimensions are perfect for a wide variety of small community fish. I just saw it at Petco and was quite tempted to get it myself!

I'm afraid there is a reason bettas are the only fish commonly available and recommended for these tiny 2-2.5 gallon tanks. You could try just having an invertebrate tank (Malaysian trumpet snails are fun to watch) and keeping some ghost shrimp. These are cheap, commonly available feeder shrimp which have lots of personality. Red cherry shrimp are more expensive but very striking with their deep red color. You can find RCS online or at forums like aquariacentral.com.

I would definitely recommend a plant for such a setup. Plants help balance aquariums - they absorb nitrate, which would build up quickly in a tiny tank, even with a very careful feeding regimen. Try something easy and floating such as hornwort or water sprite, which can be lit by a desk lamp. Java moss would work great even with just ambient light, look for it on aquabid.com.

I hope that helps, take care!
Nicole