Has anyone ever used a berlin classic without a sump? Can this even be done. If so, what's the best way to plumb it? I was thinking of somehow converting it to a makeshift hang-on type. Can it be run with a non-submersed pump (if so what brand). Or if it sat under the tank would the performance be degraded due to the long (2-3') plumbing lines. I really don't know much about skimmer performance other than the general principles. Bought this one used and would like to try it on my 30gal before I upgrade to a larger tank in the spring. thanks.....