Why do pre built sumps have a flow slot mid way down in the drain/skimmer section?

[b4tn]

I am planning my sump build and I was just wondering what the purpose is? Is this so the fuge area gets skimmed also? Is it necessary or recommended?

 

[Reefing Madness]

 

[Paulday]

I think it's for adjustability of water hieght

 

[b4tn]

Here is an example. It looks to me like the water height in the return chamber is dictated by the baffle for the return pump chamber. The only thing I can think of is so that the water in both number 1 and 2 chambers is skimmed.

 

[IotaElwyn]

Isnt that if you want to do other filtration methods instead, IE Berlin?

 

[booth2010]

Are you talking about like the fish cut out in that baffle separating the 2 chambers?

If so my guess is so that the skimmer section and fuge is separated so that the there isnt a lot of flow but water still passes between the chambers. If I remember correctly refugiums arent supposed to have a lot of flow.

 

[b4tn]

Are you talking about like the fish cut out in that baffle separating the 2 chambers?

If so my guess is so that the skimmer section and fuge is separated so that the there isnt a lot of flow but water still passes between the chambers. If I remember correctly refugiums arent supposed to have a lot of flow.

Yes! But I guess I dont see how flow will be any different vs just flowing over the edge.

 

[cbc4447]

So both sides stay a consistent level. You can use either chamber for your skimmer.

 

[booth2010]

It probably isnt that much different but how much cooler is a fish cut-out vs just flowing over another baffle? lol. On top of that if it was another baffle to flow over you would not be able to adjust the height without a baffle becoming useless, unless both were adjustable