Alaska_Phil

frankly with 2 over flows if they're going to the same section in the sump their height is only marginally important at being perfect...

You said it yourself... you're looking for 700gph flow... so 1 smaller box will cover it....

Consider that 2nd smaller overflow your emergency drain when something bad goes down... if it's a slight bit higher then oh well, just means less chance of it being clogged when your primary overflow fails to do it's job

With the template they give you, it is really easy.

I went with their 700 gph kit, and ended up that I had to butt the box all the way up to the top tank trim. If thats your case, then it would be pretty easy to get em level.

They also sent me a packet of candy...

Actually, I was thinking one would feed my algae scrubber, the other would go to the skimmer section. Then have the return in middle of the sump. But I suppose a couple of ball valves would make it pretty easy to bias the flow which ever way I needed.

Heathd, thanks for the first hand input. and Was it reef candy?

I think it was fun dip.

I would say two 700... just as others said you want to have another just in case one clogs. I am guessing you cant drill the tank? Drilling is always better...

it's always about giving yourself more options isnt it

btw checked out your other hobby maybe you can become Sarah's personal pilot up there. she could sit on your lap but would probally want some doors

Ok, just ordered 2 of the 700 gph kits. One for each back corner.

srusso: The glass-holes kits include the diamond hole saw for drilling.

DJ: Never met Palin and her husband has a much nicer plane than I. We were joking during the election that if elected it would be the first time a Piper Cub got to use the call sign "Executive One".

Originally Posted by Alaska_Phil

Ok, just ordered 2 of the 700 gph kits. One for each back corner.

srusso: The glass-holes kits include the diamond hole saw for drilling.

I am sorry! I though you where buying overflow kits! You know that one that you use for a non-drilled tank!? I would have said get only one. Maybe you still can return one?

Ahh its too late, but I would have went with the big one. no reason to give whys since you already ordered.

I thought you would need minimum 1500 gph for a 150 gal tank. Am I misunderstanding the required flow rate?

Flow rate doesnt have to be purely based off of the sump. People typically compensate with the use of powerheads.

So Mr.Phil could do 1000gph overflows and return pump, with (2) 250 gph powerheads to make the minimum requirement. With that said, rarely is 10x tank volume enough. Im sure Phil will chime in with his plans for tank flow.

For a reef tank the rule of thumb is 10 to 20 times display volume (DV) per hour of total flow. However, that should NOT be all from the sump. Check out our host's web page www.melevsreef.com for more info, but typically the sump should only see 3 to 5 times DV per hour. Otherwise, unless you have a huge sump it'll look like a white water rapids as the water blasts through there. for example in my 50 gal I have about 250 gph flowing through my 20 gal sump, and two 400 gph Koralia power heads. This isn't nearly enough flow, so I just got a Pan World 150PS pump (Holy Bat Stuff is that a huge pump!) to run a closed loop with a SCWD wave maker. This should add about 850 GPH switching from left to right.

For the 150 I haven't decided exactly what I'm going to do for flow yet. My ideal would be 3 or 4 Vortech MP40's, but at $450 each that's tough bullet to bite. So I'll probably start with 3 or 4 of the larger Koralias first.