My First Aquarium "job"

[SnowManSnow]

So the middle school next door has a "marine" aquarium that is in DIRE need of some maintenance.

I volunteered to "make it right for them"

Basic setup is about a 65g aquarium.. A middle sized PM skimmer, some sort of dual hqi and CF light, a BIG SUMP.. like bigger than the tank which is REALLY NICE.

The thing im not sure about is the CPR overflow. I was in there with the principal of the school the other day just getting a feel for it and he pulled a tube off the top of the overflow that was connected to what looks like an air pump (i have NO IDEA why she did this). The tank immediately started overflowing. The return pump was still going causeing the overflow. My question is.. why did this stop the overflow from draining water into the tank????? whats all this about?

I've always just dealt with drilled tanks or HOT equipment.

Thanks for any help.

B.

 

[Anonymous]

Many HOT overflow has that. When air get into the tube, you essentially is breaking the siphon. People use it by attach it to a venturi or a water pump (Aqualifter) to suck air out. It is essential to make sure there is very little air in the top of the overflow by constantly sucking the air/water out, esp. right after a power loss.

 

[rbursek]

Ditto,
buddy has that on his HOT, if it gets plugged or fail over flow, he has had his share, BEWARE!!!
Bob

 

[pcardone]

I have one of these. works good runs quiet. keep the suction pump and tubs clean if the pump fails it will empty your sump into the tank. I keep the vacuum pump on top of the overflow as to keep the tubing as short as possible,