If you are going to keep 6 to 8 fish in a 50g...
- make sure they are fish that stay small
- do not overfeed, but do feed the fish properly so they do not suffer
- get a good skimmer and keep it well maintained
- go BB and siphon out the crud when do weekly water changes
Personally, I wouldn't keep that many fish in a 50g, not matter if you have a skimmer, sump and refugium. They are going to make way too much waste material and you're going to have an nuisance algae problem in no time.
I totally agree with the statements about getting the best lighting you can for the tank if it is going to have corals in it. MHs are great, but VHOs can be a pretty good alternative and you can still have sps corals, ime, with them.
Here's my page on
our BB 120g that is sumpless, skimmerless. The highest tech equipment we have are a pH probe contected to a digital readout and a refractometer. Oh, I almost forget -- the turkey baster
Water chemistry test kits are also high on my list of must-haves -- alkalinity, calcium and magnesium kits are critical for optimum coral health and growth.
Here's our page on
maintaing BB tanks, in case you're interested.