ok so now how bout flow? I'd get maybe 1 powerheads, but imo, for a small 10 gallon tank, you'd be better off getting something like an aquaclear hob filter and just using it as a little fuge. Get one thats bigger than whats needed for a tank thats 10 gallons...i'm thinking the ac 70? I think it does 70 gph right? if so, i'd get that.
That will take away one powerhead that would be needed, but you still need another one...i'd get one that does around 100 or 120 gph and put it on the opposite end of the hob. That will give you a more random flow.
What i would normally say is just get at least 2 powerheads...one on each end pointing at each other, one slightly higher and to the side of the other ones flow. But 10's are just too small to where that would be kinda unsightly, you know? Thats why i say go w/the hob...you can get flow w/out anything in the tank really, along w/a fuge in the same thing
Then lighting...Do you wanna just keep stuff like softies? (xenia, mushrooms, gsp's, etc?) or do you want to keep the harder sps type stuff? If this is your first reef i wouldnt suggest doing sps, specially in a small 10 gallon, because they're generallyy harder to grow in smaller tanks because they're not as easy to keep stable. But if you're really good about keeping up with the tank and stuff...then you could get sps corals..at which point you're gonna need much stronger lights than what softies and lps need
So for softies...i'd say maybe a 65w fixture at min....but theres one that is on doc foster and smith thats the right size of a 10 gallon tank (20 inches right?) and its a 2x40 light bulb fixture. IMO, that would be better cuz you could also have the actinic instead of using a 50/50 which will lower your PAR. I'm sure some people keep stuff w/a single 50/50 65w bulb on a 55, but imo, 50/50 kinda limits what you can do.
If you want an sps tank, you're gonna need stronger light, but i'm not sure which ones would be good for just a 10...many people go with mh's only for sps corals, but t5's can be just as strong
So what type of reef would you like?