Plumb internal overflow

[frank10]

I'm setting up my 150 reef ready tank

It has two internal overflows.

Each has two holes at the bottom.

How should I set these up? One for return and one for drain in each internal overflow?

 

[SlipperyWhipple]

I would do one drain and one return in the first one and then one return and one emergency overflow in the second assuming they are on opposite sides of the tank. It’s important to have an emergency overflow so as to not risk flooding your house in case the original overflow gets blocked somehow.

 

[Hallowhead]

Very interesting ...

I would have a return in both to increase flow.

The other two I'd do a Herbie:

One with a full siohon below surface with a gate valve matching return flow and the other one an emergency

 

[frank10]

Thank you for the advice

what if I did a gate/herbie and emergency return in each and did one or two returns over the side?

also, do I need seperate drain lines for emergency and non-emergency drains all the way down to the sump?

the prior owner had a return and a durso in each

the internal overflows are offset from the cordners a bit

 

[Hallowhead]

Thank you for the advice

what if I did a gate/herbie and emergency return in each and did one or two returns over the side?

also, do I need seperate drain lines for emergency and non-emergency drains all the way down to the sump?

the prior owner had a return and a durso in each

the internal overflows are offset from the cordners a bit

I wouldn't do two Herbie's

I would do a bean animal than..

1 with full siphon and gate valve
1 with durso head
1 as emergency
1 return
Second return plumb up and over

A durso alone is loud

 

[Rjramos]

I have always done one in usually 3/4” and one out through a durso. I always hear people saying, “What if your out gets clogged?” In 25 years of reef tank overflows, I have never had a clog. I put covers on top of overflows to prevent snails from going in there, anything smaller getting through the weir will end up in the sump. Some people place intake screens on the durso opening, I don’t, as these can get clogged by algae or smaller debris.

 

[Hallowhead]

I have always done one in usually 3/4” and one out through a durso. I always hear people saying, “What if your out gets clogged?” In 25 years of reef tank overflows, I have never had a clog. I put covers on top of overflows to prevent snails from going in there, anything smaller getting through the weir will end up in the sump. Some people place intake screens on the durso opening, I don’t, as these can get clogged by algae or smaller debris.

I need to put a cover on my overflow... More recently my six line found a little opening and jumped through and ended in my sump. It's finding nemo part 3. lol