[flamingo]

Okay heres some pointers from my experience and my cousins:

1. Ottos do not need to be kept in groups. They can be kept with dwarves since most of the time the puffers won't really even notice them. Some people have had theres killed but from the ones i've had this was never a problem.

2. Like you said, only 3 if you have them in a 10 gallon. That may seem like nothing due to they're size. My cousin put 5 in his 10 when he first tried them. Not a good idea, within a couple days he had i think 2 or 3 left.

3. Don't keep them with bigger fish. The puffers suprisingly will most likely attack or "fin ride" on them. My cousin had a kissing gourami with his and they would bite and hang on to its fins and take a little ride.

4. Don't have strong currents or suction from a filter. This may sound wierd but when i had some a while back i had a strong filter and they got stuck to the filter intake lol.

5. Be very picky on tankmates. Thye only ones i've gotten to work are kuhli loaches,ottos, and one time a molly.