Intake question

[thatkarelguy]

I'm getting the impression that its best to pull water off the top 1-2" for filtration. Why is this? or does it really matter?

 

[liv2padl]

in a freshwater tank, we pull water off the bottom and return it to the top to insure good circulation. protein skimmers do take water off the top. i''m not a saltwater guy and am as interested in this question as you are.

 

[Reefscape]

One of the main reasons is so only a minimal amount of water is syphoned back down to the sump in the case of overflow problems...

If your refering to skimmers, the majority of unwanted waist's are collected at the suface, hence the term " Surface Skimming "..

Not exactly quite if this is what you after, but, that is how i read your question...

Niko

 

[thatkarelguy]

I'm more interested in the filtration effects rather than plumbing considerations

 

[fsn77]

In a reef tank or FOWLR, the live rock is intended to be the main filtration. That said, the removal of surface water down to a sump has a lot to do with avoiding potential plumbing problems.

 

[Max]

Yup , and skimming but, the rock and sand does almost all of the filtration. It really won't make a difference other than in plumbing because all of the water out side of your rocks/sand is fairly uniform chemically unless you have almost no water movement.
cheers
Max

 

[joebcarr]

i wish i had the link, but i've read somewhere that harmful things collected on the top, some kind of toxins maybe...

i'll keep looking for the link