Now I understand the problem clearly. You cannot siphon water from the tank without a HOB overflow (a box on the inside AND on the outside). It doesn't matter what pump you buy, you'll never be able to equalize the flow between the two, even if you match it up perfectly one day. Each day the pump will build up slime, electricity rates vary coming out of the wall, the pump ages, etc. What works this minute might not in an hour. And what if there is a termporary power outage? That would be a mess.

Pondmaster pump? Some of those are perfectly fine for our systems, such as the Mag pumps. http://tinyurl.com/yr7oes For your situation, a Mag 18 with 1" to 1.5" plumbing rising up 18' would be more than enough pump, probably too much for the overflow we've discussed. Many people make the mistake of screwing on plumbing that matches the pump's threads (Mag 5 - 1/2" needs 1" plujmbing; Mag 9.5 or 12 - 3/4" needs 1.5" plumbing; Mag 18 or 24 - 1" needs 2" plumbing) which restricts the flow that pump produces.

For 9' head height, I'd get a Mag 12 with 1.5" plumbing, personally. I don't like exceeding what a 1" drain can handle. It needs to be enough flow to push the bubbles through the U tube of the overflow, but not more than the box can drain.

And in regards to your question about sound, no that box is dead silent. There are methods that can be employed to assure silence. Here's more about the plumbing (scroll down on this page) on that sump: http://www.melevsreef.com/install_sump.html