Opinion on return lines plumbed to bottom of tank

[Gundy]

I am building a peninsula tank 84x36x28 and about 350 gallons. I do not want to place power heads on the short side of the tank but know I won’t get good flow without them. I will have 2 Cor 20 pumps as return pumps and thinking of running the return pipes down the inside of the tank and then elbow to the bottom of the tank with 2 outlets on each line. So instead of having the returns exiting at the top of the tank, the PVC will be hidden in the sand and I will hide the return line elbows with loc line fittings rising up about 6-8 inches with rock. I will put several power heads on the other short wall for flow. Do you think I will get good flow from this? Is this a good idea?

 

[Glenner’sreef]

Sounds doable.

 

[SudzFD]

I am building a peninsula tank 84x36x28 and about 350 gallons. I do not want to place power heads on the short side of the tank but know I won’t get good flow without them. I will have 2 Cor 20 pumps as return pumps and thinking of running the return pipes down the inside of the tank and then elbow to the bottom of the tank with 2 outlets on each line. So instead of having the returns exiting at the top of the tank, the PVC will be hidden in the sand and I will hide the return line elbows with loc line fittings rising up about 6-8 inches with rock. I will put several power heads on the other short wall for flow. Do you think I will get good flow from this? Is this a good idea?

It sounds like a very cool idea. Just realize a couple things. If your return pump fails it will drain your entire tank. Make sure it has one way check valves to prevent this.

Also make sure your return pumps can overcome the head pressure of the water. It should be about .5 lbs per foot if depth.

I’m sure every pump out there for a tank this size can overcome that, but it’s certainly something to consider.