[Crosby87]

I'm going to be setting up a 90 gal FOWLR with a sump/fuge. I had my LFS drill the hole in my tank so the water can flow down into my sump.

They said I should get anywhere between 400-500 GPH to my sump. I want to add a protein skimmer to my sump, but don't know what size to get.

I'm on a budget, and read some good posts about the odyssea skimmers, so I'm going to try one of those for now.

They have 2 models, one skimmer that is rated for a 75 gallon tank, and another rated for a 160 gallon tank. I'm also going to add my Remora hang on back skimmer after I take my 55 down.

Would I be able to use the 160 skimmer that 500 GPH in my sump, or go with the 75 that does 315 GPH.

Thanks in advance.

[leebca]

I know you really don't want to make this complicated, but I'm afraid that doing it correctly IS complicated. Thanks for posting!

There are no standards set on protein skimmers. A manufacturer can claim whatever they want to claim in regards to what size marine system it goes with. In general, if you don't know the flow rate (I'll get to that in a moment) then it is best to get a skimmer that is rated for 2-3X the system volume. So if your display will hold about 85 gallons and the sump will be holding about 15 gallons when the system is in operation, then you need a skimmer that is 2-3X 100, or suitable for a 200 to 300 gallon tank! See how much the manufacturer can be 'off?'

Now let's talk the real measurement you need--how much water does the skimmer need to process. I am quoting from this post:
What is Water Quality

The optimal target is to have a skimmer that will process about 1.5 times the volume of water in the entire marine system, every hour. As an example, for the average bio-load system with a total volume of 115 gallons, the skimmer should process no less than 160 gallons per hour. There is no ‘standard’ skimmer rating system, unfortunately. Most manufacturers will stretch their product’s skimming ability, so it’s hard to give advice to the aquarist on what to buy. If the processing gallons per hour is not specified by the manufacturer, then in general, I recommend the aquarist purchase a skimmer rated between 2 and 3 times the volume in the system. So if the system contains 115 gallons as in the above example, the skimmer should be rated for about 250 gallons. After its choice, it must be operated to its full efficiency. Don’t reduce the recommended pump flow; keep the air intake clean and open; keep the bubble chamber walls clean and the collection cup clean. The skimmer only works best when it is clean. How often to clean? No less than every other day.

You will need to get, from the manufacturer, 'How many gallons does the skimmer process per hour' figure. Then you can choose the correctly sized skimmer!

Now that you have that, you don't have to worry about how much volume is passing through the sump, though a high number is desireable. This is because the skimmer draws from the sump and returns water to the sump. So the volume of water the skimmer processes is not connected to the flow in the sump. Is this clear?

[Crosby87]

Lee, thanks for the great post. The total gallons in my system would be around 110, 90 gallon display, 20 sump. I'll check out skimmers that are rated for 220 and up.

[weez1959]

Originally Posted by Crosby87

The total gallons in my system would be around 110, 90 gallon display, 20 sump.

You may not have as much water as you think in your system, you have to take into consideration the sand and rock you will have in the tank.
As an example, I set up a 90 gallon tank with a 35 gallon sump. With rock and sand displacement, I have 82 gallons of water total!
But going back to the skimmer, you're better off over estimating

[Samper]

If you're on a budget I'd reacommend the coralife superskimmer. A few members of our reef club here in Ar run them on some beautiful systems. The biggest I've seen is a 180 and I personally feel it needs a slightly bigger skimmer but the tank looks great none the less. My partner runs one on a 125 and he has hands down the nicest tank in the area. Good luck.