Skimmers & Water Level

 

I just set up my first systems with a skimmer a little over a month ago. It's a 50+ gallon frag tank a 50+ gallon sump/refugium and a 28 gallon Nano all plumbed together. I designed a skimmer section for this system using a 20Gallon tank because I want to feed the corals liberally to promote growth and the skimmer helps me do this without as much worry about excessive nutrients in the system.

 

A properly designed sump can support a skimmer using baffles only with no ball valves or other equipment. In fact the addition of additional equipment in a sump adds complexity and the chance of failure somewhere. It's easier if you don't have a refugium in your sump but it can be done with a refugium as well. 

 

There are many ways to configure a sump and skimmer and the best way for your tank will depend on what you want in the sump and the space inside your stand particularly how much height is available. You can also get a ball valve from Home Depot or Lowes for less than $10.00 and tee off the overflow plumbing so that a portion of the water goes to the skimmer section located at the return end of the sump, bypassing the refugium. This way you can get the most water volume in your sump and still keep the baffle for the skimmer low enough that you don't have to raise the skimmer up in the sump. This is particularly useful if you have limited space under the stand.

 

Once you decide how to configure the sump put your float switches or valves in the return section along with the return pump. This will regulate the water level in that section and balance the rest of your water in the tank and sump. Until recently I also used a reservoir for my Top Off RO water. I had a 6 gallon container and an aqualifter pump that would go for a week to 10 days between refills. This works great when you can't tap directly into the RO System and is actually safer because the most water that can be pumped into your system if something fails in the on position is 6 gallons. While direct connected systems can be made very safe there is always the possibility of water continually being pumped into the sump diluting your saltwater and possibly causing a flood.

 

Because there are so many different ways to configure a sump, Skimmer and ATO you need to decide what you want to accomplish first then work your design around your goals. The simpler the better IMO but don't rush this part of the system. If you plan it out and think of how it will work and what happens if something goes wrong you can design a sump that will work well for you.