Preventing overflow from tank to tank.

[rustyj]

I have a 20 gallon plastic container (safe and clean for this use) that is approx 12Wx18Lx36H that i would like to use as a refugium for a 135 gal reef tank. I want to maximize as much additional water to help keep the system stable. I am most concerned about preventing an overflow from one to the other. Do you use a float cutoff valve or backflow check valve? Do I need to just ensure that the return to the tank is not in the water (I dont need it for circulation) so if the pump in the refuge shuts off it will not reverse syphon? If I can prevent one side from syphoning and use an overflow than only the amount in the overflow will be I will have to worry about in the refugium? Does this sound right? I would like to make the process from the tank to the refuge back to the tank again a slow process giving time for both macro algae and anarobic bacteria utilization of any excess nutrients and to convert the nitrate to nitrogen gas and oxygen. How could this be accomplished not having to continually move water from one to the other, any suggestions? Thanks for your help.
Rusty

 

[dogstar]

Keeping the return out of the water will stop the siphoning back to the fuge. Most people run their return under the water to stop splashing ect and ....just drill a small hole in the return at or just below the running water line and when air enters the hole in a power failer, that will break the siphon. Just do some testing and find out where the safe level is to top off the fuge because thats were the evaperation will show up at now.

 

[rustyj]

Originally Posted by Dogstar
Keeping the return out of the water will stop the siphoning back to the fuge. Most people run their return under the water to stop splashing ect and ....just drill a small hole in the return at or just below the running water line and when air enters the hole in a power failer, that will break the siphon. Just do some testing and find out where the safe level is to top off the fuge because thats were the evaperation will show up at now.

Thanks, I will take a stab at it this week.