saltywashington
Member
What do you wonderful people recomend for an overflow rate on a 55 gallon reef tank?
Overflow rate for a 55 gallon reef?
- Thread starter saltywashington
- Start date
saltywashington
Member
Thank you so very much.
saltywashington
Member
So the idea would be to have a returm pump that is rated at a higher GPH then what you are overflowing. When you are all said and done the adjustment would be made on the pressure side of the return pump?
melbournefl
Member
Yes, all "restriction" to a pump should be made on the return line rather than the input line.
Good luck,
Paul
Good luck,
Paul
oceanjumper
Member
I'm not sure if you understood it correctly, saltywashington. Just to elaborate:
Imagine a power failure. Your sump is full with water (of all the water that drained down). Power goes on again. Return pump pumps at full capacity (say 1000 gph). If overflow box in the main tank can only handle 700 gph.....300 gph too much is pumped into the main tank: FLOODING is the result...
So, you want a lower GPH return pump than your overflow box.
Cheers
Imagine a power failure. Your sump is full with water (of all the water that drained down). Power goes on again. Return pump pumps at full capacity (say 1000 gph). If overflow box in the main tank can only handle 700 gph.....300 gph too much is pumped into the main tank: FLOODING is the result...
So, you want a lower GPH return pump than your overflow box.
Cheers
oceanjumper
Member
Or, do you want a higher GPH on the pump and make a T back into the sump? That way you can release/adjust the flow to your tank? That would work as well.
saltywashington
Member
The reason I ask is, the stuff that I got from my dad seems to be backwards. The overflow is faster then the return pump that was included so I have had to restrict the overflow box. I have not been able to get a new pump yet.
broomer5
Active Member
saltywashington
It's true that an overflow can be RATED or HANDLE more flow than a given return pump ~ but it's impossible for the overflow to be "faster" than the pump.
The overflow can only "overflow" as fast as the pump pushes water into the tank.
If your overflow is grossly oversized for the pump, or the pump is grossly undersized for the overflow - all you'll get through the overflow may appear as a trickle.
A trickling overflow will work - but you run the risk of getting tiny air bubbles accumulating up in the top curve of the U tube.
As these bubbles accumulate into on large air gap - if allowed to continue - this air gap can grow large enough to cause the U tube to "break siphon", which leaves it inoperable.
The return pump doesn't "know" this has happened, keeps on pumping, and the tank level will rise to the point of overflowing it's rim.
Results - wet floor and empty sump / burned out pump.
If this happens - and you're not there to catch it, you may lose living creatures too if you're relying on a wet/dry biofilter or heater in sump.
You should not have to valve the draining lines from the overflow.
You can if you wish to - but it should not be necessary if everything's balanced.
Rule of thumb: You should select the return pump so it's maximum flowrate at the installed head pressure is just slightly LOWER than the maximum flow rating of the overflow.
It's true that an overflow can be RATED or HANDLE more flow than a given return pump ~ but it's impossible for the overflow to be "faster" than the pump.
The overflow can only "overflow" as fast as the pump pushes water into the tank.
If your overflow is grossly oversized for the pump, or the pump is grossly undersized for the overflow - all you'll get through the overflow may appear as a trickle.
A trickling overflow will work - but you run the risk of getting tiny air bubbles accumulating up in the top curve of the U tube.
As these bubbles accumulate into on large air gap - if allowed to continue - this air gap can grow large enough to cause the U tube to "break siphon", which leaves it inoperable.
The return pump doesn't "know" this has happened, keeps on pumping, and the tank level will rise to the point of overflowing it's rim.
Results - wet floor and empty sump / burned out pump.
If this happens - and you're not there to catch it, you may lose living creatures too if you're relying on a wet/dry biofilter or heater in sump.
You should not have to valve the draining lines from the overflow.
You can if you wish to - but it should not be necessary if everything's balanced.
Rule of thumb: You should select the return pump so it's maximum flowrate at the installed head pressure is just slightly LOWER than the maximum flow rating of the overflow.