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In sump skimmers: how deep?

Moe_K

Stabbed by Foulke
I have an ASM G4 skimmer in my sump.
The sump is a 100g Rubbermaid farm trough.

At first I had the skimmer about 16 inches under water. The water level in the sump was up to the taper on the skimmer. Neo said that was too deep, and advised me to build an egg crate stand to raise the sump.

So I did so tonight. Now the skimmer is only about 6 inches submerged. Too early to tell how the performance will be effected.

Where does the sump's water line come to on your skimmer? Is there a target depth for these things?
 
Target depth depends on the skimmer. Mine advises that the return should be above water level but it is just below and still functions well. It is a PM bullet 1 but it is already raised as high as I can under my stand. I believe euroreefs are recommended to be no more than 8" or so below the surface. I would think the ASMs are similar since it is basically the same skimmer.
 
Dumb question Moe, but did you check the manual for your skimmer? I know the manual for my Reef Devil states that it should only be submerged in water up to 7" deep, and the outlet is at or slightly above the water line for "best action".

I'm sure it depends on the skimmer though.
 
I thought the problem was if the skimmer is submerged too deep then it is more difficult to maintain a consistent water level inside of the reaction chamber.
 
I have my ES5-3 on a 5" stand. IIRC Euro-reef/ASM reccomend skimmer chamber water height being in the ~6' range. I think a real high water level limits your ability to skim dry, and a real low level adds extra head to your pump.
 
Dumb question Moe, but did you check the manual for your skimmer? I know the manual for my Reef Devil states that it should only be submerged in water up to 7" deep, and the outlet is at or slightly above the water line for "best action".

I'm sure it depends on the skimmer though.
Yeah, ASM's don't have much in the way of instructions. :o :p
 
My G6 is submerged just enough that the top part of the elbows are just breaking the surface of the water. Any deeper, and it over flows on me.
 
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This is a problem for all sump skimmers because the water level in most sumps is not constant because of evaporation and top off and the head on the pump is changing. I am building a custom sump with skimmer and fuge area where the water level is constant and water loss shows up in a 5 gallon heater/return pump area. I have a CSS65, it skims well. What have I done until new sump is ready? After finding the right water height and skimmer adjustment I put a "max" mark with marker on sump. I fill sump to that level daily to that mark and leave the skimmer alone. The skimmer is now "set it and forget it."
 
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Moe, put the skimmer as shallow as the pumps will allow without sucking a water vortex. This is the least amount of head on the pump....as long as your top off is consistent, then the water level should maintain. If the sump water level drops too much, the pump runs dry and cavitates.
 

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