Help setting up a 40b

ok, I am sure loads of folks on here will be happy to help...

First up, flow in your main tank.

For softies and lps I'd suggest a turnover rate of 30x. That means 1200gph.

Let's say the distance from your sump to display tank is four feet. The mag 3 will give you around 300 gph. So you are looking for supplementary water movement. You want turbulent water so that the coral is getting fed from all sides. This could mean two or more smaller powerheads. Personally I'd go for a jebao wp25. If you feel like one is not enough, you could get another one pretty cheaply and place it at the other end of the tank.


The flow rate through your sump should not exceed your skimmer (if you are going to have one). 300gph through the sump would be fine.

A 1/2 inch return , and one inch drain both sound good. You could go with pvc, or flexible tubing. Tubing means less vibration.

In front of your drain hole you'll want an overflow box. This will help remove surface scum, and keep the drain line noise down. I'd suggest a glass-holes nano-con diente overflow. There is a calculator on reefcentral which will tell you how much water to expect to drain into the sump when the power goes out. This will determine how dry your floor will be!

hope that helps.

Yep, go with the 700 gph overflow. That is a better choice than the nano con-dientes. Also it never hurts to go larger with pipes. Fluid dynamics and all that.

Here is how I would determine the hole placement. Put the overflow box against the glass. The top of the overflow box should be about an inch from the top of the tank. Then using a sharpie you can mark your drill hole.

You can set the water level in your sump to whatever you like. As long as your drain line is bigger than the return, all will balance out. Use an ato unit to keep everything at the level you want. There is another calculator which will work out how much will drain into the sump in the case of a power outage.

You can have as much or as little water in your sump as you like. As long as it covers your return pump everything will be ok. If you choose a skimmer that likes to sit in five inches of water, and you want to have a nine inch water level then you can use egg crate to build a little platform.

As for drilling holes, I think the general rule of thumb is at least one hole diameter away from any other edge or hole.