Sumps

Greater Flexibility - maybe

Easier maintenance - No if you are already using a good sand bed

It's great to use a "sump" if you are interested in growing other kinds of organisms. For several years I had a 25 gal. in the window leading to a 20 on the top of a stand leading to a 10 at the bottom which was unlit and grew sponge and tunicates like crazy. The window tank had lots of algae, coral and even acropora mostly lit by direct sunlight. The middle tank was a fish only.

Drilling tanks can be disastrous. A simple overflow can be made from a U-tube, pvc pipe and a Lees specimen box that fish stores use to hold your fish after catching. It is important to look at the way the water acts during and after a power outage. You can totally avoid a flood or risk always having one. It's your choice. I would be glad to share but it's very late and I'm sleepy. Call or write if you want more info from me.

Mark  296-1563  [email protected]

Sumps are great.  If your tank is doing good I would keep the tank how it is.  If you do want to setup a sump I would recommend drilling your tank.  I know you wanted advice other than drilling, but in my opinion other options can have problems.  The biggest problem comes with the "hang over the back overflows".  These overflow boxes allow you to move water to a sump by means of siphon.  The two biggest problems are draining too much water from you top tank when the power goes out and spilling water on the floor, and overflowing water in your top tank if the siphon somehow stops.  Although there are techniques to stop both these problems, the often fail.

I used there types of overflow boxes for many years, but always ran across problems.  Sometime my tank would go for two years without a problem, but the day you come home to water on your floor you will be sorry.

This is just my experience.  I know people that have never had a problem.  I lost many nights of sleep hoping that my tank wasn't spilling onto my floor.

Just my $.02.