30 gal (I think) reef tank

[philolsen]

I just got this 30 (I think) acrylic bow front reef tank with a built in sump, I have never had a tank this small, but I got the whole set up including a Finnex 110 watt PC fixture for FREE. Heres my questions:
1) What do you recommend for the skimmer, it only has a width of 3 7/8"?
2) What size return pump do you recommend

[Reefland]

Would it be possible to hang a skimmer on the back of the built-in filtration?

[philolsen]

I would be close, the water level looks like it might just make it. I was thinking about drilling the back of the tank and using a external skimmer, any suggestions?