Return Pump Challenges

[Morpheosz]

My 75g is about a year old and I have dialed in everything except the return pump. I am on my 3rd return pump setup and am pulling my hair out a bit. My situation is that the tank isn't very large so I don't need a lot of flow (shooting for around 4x turnover on 95g of total volume) but I have the sump in the basement so there is a lot of head pressure necessitating a significantly oversized pump.

I started with a pair of Current-USA Eflux 6010s running together in the hopes of having redundancy in case of a failure. I quickly ran into issues with the flow varying quite significantly over time, making it impossible to dial in my gate valve. Individually each was only just able to overcome the head pressure and combined deliver around 300gph. I assumed given they were running so close to the margin that they were struggling to give consistent flow and / or fighting each other so I pulled the plug on those.

Next I bought a Jebao DCP-10000, thinking let's try one bigger pump. This one was able to shoulder the load and deliver 400ish gph just fine. However, similar to the Eflux, over time it would periodically have a step change in output and drop by 10%, give or take, for no apparent reason. Every time this happened my return would start sucking in air making noise / mess and I'd either have to tinker with the pump until it resumed normal output or adjust the gate valve (always having to adjust it again later when it resumed normal operation). It would happen every few days and was very annoying and made it impossible for me to confidently leave town for a couple of days.

So I finally decided that maybe I was cheaping out and bought a Vectra M-2, assuming that Ecotech was a gold standard in pumps and powerheads in our hobby. However, with this pump the controller is flaking about once a week where for no reason it just cuts power for a few seconds at a time, sometimes getting into a repeated pattern of it. Also the flow has also experienced some step changes similar to the Jebao.

So needless to say I'm pretty frustrated at this point as this is the one part of my setup that I haven't been able to dial in and rely on. I'm curious if people have had similar issues or any suggestions. Is it unrealistic for me to expect consistent output from a return pump? Is the head pressure the wild card (based on my output, I'm guessing I have about 15' effective)? Choice of pump? Should I get an L-2, something considerably overpowered and run it at a lower speed?

 

[YOYOYOReefer]

Get an AC pressure rated pump like an iwaki and you wont have these issues.

 

[Morpheosz]

Get an AC pressure rated pump like an iwaki and you wont have these issues.

I believe all the Iwaki are external? I don't have room to plumb in external pump without a lot of reconstruction. Any submersible equivalent recommendations?

 

[theMeat]

Have had the same problem on a few different tanks with basement sumps. Like you tried a few different brands, and tried oversizing. It didn’t work. Or I should say they did work at first, then in a few months time the gph fell off. Think you should go with an iwaiki or other high pressure pump. They will make more noise for sure, so plan for that, trying to isolate with rubber mat and the likes

 

[YOYOYOReefer]

nope they are external pumps for sure...
ive had same issues you have with the dc pumps seeming to be inaccurate flow rates when you put some pressure on them. They just are not as strong... I do like the bigger jeboa's dct pumps but i would say they all seem to drift a bit.
i tried some dc pumps on my quad beckett skimmer and none are anyhwere close to set and forget like the current dual iwaki 70s have been for the last 15 years.

 

[mfinn]

Unless you went to a expensive high pressure pump like some of the Red Dragon pumps are, I would suggest you go with a AC pump like maybe a Fluval SP6 or Sicce HF 12. Not sure exactly what the head pressure you have, but something like these would maybe work.

 

[theMeat]

Agreed. An ac pump, even if not rated for high pressure, would be a better more consistent choice, if you cannot figure an external high head pump into the plan

 

[Lbrdsoxfan]

Get an AC pressure rated pump like an iwaki and you wont have these issues.

This. With the head your pumping, DC doesn't cut it imho.

 

[Morpheosz]

Seems like a quick consensus is forming, thank you all! Maybe I'll try a submersible AC before going down the major construction path with an external.

 

[Morpheosz]

Seems like a quick consensus is forming, thank you all! Maybe I'll try a submersible AC before going down the major construction path with an external.

To that end, any suggestions for a submersible AC worth trying would be welcome

 

[YOYOYOReefer]

MAG 36 is a good internal pump for your application.. i bet it would be ideal

 

[Lbrdsoxfan]

MAG 36 is a good internal pump for your application.. i bet it would be ideal

This. Mag 2400 or 3600 would be my choice.

 

[theMeat]

Yup. Ehiem would be my first choice for an AC pump but the head high just isn’t there for you. Danner Mag Drive are not the most refined or quiet pump out there but for your head height would be my choice as well

 

[Morpheosz]

Great, thanks everyone, I'll give it a shot!

 

[Morpheosz]

Yup. Ehiem would be my first choice for an AC pump but the head high just isn’t there for you. Danner Mag Drive are not the most refined or quiet pump out there but for your head height would be my choice as well

I don't need much refinement - I just need it to pump consistently, at one speed Also noise isn't a big issue as the sump is in my laundry room.

 

[YOYOYOReefer]

mags are loud and add heat, but if you must go internal pump they do tend to last,and have replacement parts available. But wont be as good as an iwaki or pan world external pump...how hard would it be to replumb it?

 

[Morpheosz]

mags are loud and add heat, but if you must go internal pump they do tend to last,and have replacement parts available. But wont be as good as an iwaki or pan world external pump...how hard would it be to replumb it?

Not completely out of the question. I’d have to build a separate stand behind my sump most likely. Space to the right is already tighter than we like for access to the washing machine.

 

[theMeat]

Not completely out of the question. I’d have to build a separate stand behind my sump most likely. Space to the right is already tighter than we like for access to the washing machine.

Have you established max sump water level to avoid flood? By simulating a power outage? Those water levels look high to me.
Nice set up btw

 

[Morpheosz]

Have you established max sump water level to avoid flood? By simulating a power outage? Those water levels look high to me.
Nice set up btw

Thanks! Yes, I have cut the power many times, and the current misbehaving pump has done it for me I use a check valve on the return to minimize the backflow of water. It only goes up ~2-3" when I cut the power. It's a big sump for the tank - 34g on a 75g tank.

 

[Kodski]

I have a very similar setup so I'll chime in. I have an 80gal display in my office with a sump in the basement a floor below but also about 15ft offset from the tank. I hemmed and hawed a lot over my pump choice, I considered every option. Ultimately I came to the conclusion of a Sicce SDC 9.0 DC pump. In fact, I bought it last Black Friday. I'm happy to say I got it right. This pump is awesome. Aside from some of the very pricing options like Red Dragon and Abyzz, this was the only other pressure rated DC pump I could find. I doubted its rating at first but it has proven itself to handle my system just fine. Its very powerful, easily pumps water to where I need it. In fact, I only run it at 38% because any more powerful and the system can't handle it. I clean it regularly every 3 or 4 months or when the pump maintenance notification goes off. If I notice a dip in flow rate, I can usually get by a few weeks by jump upping the flow on the app. For more details you can go check out my 80 gallon build thread, but I can guarantee this pump will solve your issues.