4ft Tank with 1 or 2 overflow?

[Earthborne]

Hi, doing planning for future reef tank design. Would like to know if reefers here recommend 1 or 2 built in overflow for a 4-5ft tank?

btw, what's the pros & cons of built-in overflow Vs external overflow design (or siphon box design)?

[Solo77]

usually see one but if you go RD, their deltec tank got 2(hope i got it right) which is neat. One for filtering and the other for probe placement, etc. Whether in or out, think in is safe but take up tank space....and out runs the risk of leak but doesnt take up yr tank space....

maybe you want to ask good to have just one return or two ......

All the best in your design.

[davidluvfishes]

Hi, doing planning for future reef tank design. Would like to know if reefers here recommend 1 or 2 built in overflow for a 4-5ft tank?

btw, what's the pros & cons of built-in overflow Vs external overflow design (or siphon box design)?

For a 4-5 ft tank, 1 built in overflow should suffice. If you need faster water back to sump, you can have 2 return pipes in overflow..but your overflow box will be bigger.. You will need to see what you want..

Pro: An external overflow will provide more tank space as space will be taken up by the internal overflow. It is sometimes diffcult to hide the internal overflow and some may not like it as they cannot create a natural view.

Cons:Tanks with external overflows are more expensive than those with internal overflow.If workmanship is bad, as the tank ages, higher chance of water leakages. ( low possibility though)

[Earthborne]

thanks for all your replies. I think 1 shd do too. However I notice that some internal overflow has the overflow piping higher (ie water fills up atleast 3/4 or half of tank height) while some have it short with just an inch of water. So have bio-balls filled up while some is plain empty. Any rationale for such schemes?

[[V]tEc]

thanks for all your replies. I think 1 shd do too. However I notice that some internal overflow has the overflow piping higher (ie water fills up atleast 3/4 or half of tank height) while some have it short with just an inch of water. So have bio-balls filled up while some is plain empty. Any rationale for such schemes?

when ur water level is higher, u will have softer "waterfall" sound