return pump question


Active Member
BRS Member
I've seen it mentioned that it's a good idea to have TWO return pumps in the sump (since they will
eventually fail). As far a the plumbing goes would that involve two independent pvc lines back to two independent return
nozzles?? OR the two pumps pvc lines merging together into one pvc line on the way back to a single return nozzle??


Well-Known Member
BRS Member
IMO if your setup is 1 return than 2-1 but if it’s 2 returns you could do one on each. Up to you on how you want to setup. Either way you adjust your return or returns for your desired flow back into main DT. Good luck and redundancy does go a long way.
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2019-2022 BRS BOD
BRS Member
I personally have 1 with many power heads. I also keep a spare return pump on hand. just my 2 cents as your sump fills up with equipment quickly and (2) return pumps can really fill up your return chamber and make it tough to access and clean. I also have the ATK in that chamber and a backup heater so it is pretty tight with the just 1 pump.


Well-Known Member
BRS Member
IMO, the lesser the plumbing, the cleaner and easier the tank will be to maintain. With that said, by all means buy 2 identical return pumps and keep one on the shelf and it will be a matter of minutes to replace and get the system going again. As for running dual pumps, you’re wearing both pumps as they run. Although highly unlikely, there’s still a risk of both of them failing at the same time or about the same time. Even if you decide to run half power on the dual pumps, its still just twice as long before both wear out, again about the same time. A new pump on the shelf assures your system be back in action in matter of minutes. Happy reefing!


Well-Known Member
BRS Member
There’s a list of things you don’t want I have fail in the middle of the night on a long weekend. It always pays to have a spare return pump, heater, and power head beyond what’s in your tank. You don’t need to wire them up or run them all the time, but it means you can replace a failure right when you find it. For things like return pumps, you may have to clean/service them every 3-6 months anyway and you can rotate between two units while one is being cleaned.


Well-Known Member
BRS Member
All good points, so I guess it depends on available real estate in your sump and what degree of redundancy/safety you want for your tank. I travel for work during the week and have only my Apex for monitoring, so my plan uses 2 pumps to reduce the chance of ZERO return to the tank during a failure. While its great to have a spare for any critical component, that spare won't replace itself or send any heat to the tank if your heaters are in the sump. I imagine its anyone's guess how long your livestock can take it and of course add the time it takes to realize something is wrong.....risky in my opinion.
So here's what I'd recommend, if your single return line flow is good and in proportion to what your overflow can send back to the sump......keep it. I would use 2 pumps that merge into a T or Y PVC fitting connected to your existing return. What is critical is both pumps should have individual check valves in case of failure. The reason is the functioning pump will cause backflow through the stopped or broken pump and not pump it back to the tank. This set up also allows you to remove a pump for maintenance or replacement without completely stopping return flow. In my case, if the flow sensor in my return line detected a 50% reduction in flow, I'd get an alert from the Apex that something was wrong of course, but I'd still be getting heated water from the sump at approximately half the GPH flow before a pump failed.

It let's me sleep at night......even clear across the country!
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Saturday March 5, 2022
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