pressure rated submersible pump?

[reedman]

I'm thinking of using the penductors when I install my sump and as such am looking for a pressure rated return pump that is submersible. Does anyone know of any?

 

[dnjan]

Don't you need a lot of pressure and a lot of flow for those to work effectively? Good luck with the submersable option! I would think you would have heat problems with such a pump (if you can find one).

 

[lizardarm]

i might be wrong, but i think i remember reading that little giant pumps can be used in higher pressure situations.

 

[reedman]

Just need a lot of pressure, flow is less important as it is magnified by the penductor. They are designed to work at 10 psi, so it is pretty high back pressure on pump to optimize the penductor. That's not to say they won't work with a lessor pump, but you add alot of wear and tear on the pump and don't maximize the effectiveness of the penductor.

 

[lizardarm]

reed,
is this penductor the same as an eductor?

 

[reedman]

Yep. It's a shorty version of the eductor. less invasive

 

[esmith]

Hey Reed...you got any links to those "penductors"? Sounds interesting.

Eliyah

 

[reedman]

They even cater to us saltwater nuts...

http://www.kthsales.com/website/Misc/hello_salt_water_enthusiasts.htm

 

[esmith]

Do you specifically need a pressure rated pump to run one of these, or do you just end up with better performance and don't burn up your pump if you do?

So when are you finally going to be setting up the sump...???

 

[dnjan]

Just need a lot of pressure, flow is less important as it is magnified by the penductor. They are designed to work at 10 psi, so it is pretty high back pressure on pump to optimize the penductor. That's not to say they won't work with a lessor pump, but you add alot of wear and tear on the pump and don't maximize the effectiveness of the penductor.

400 or so gph at 20+ feet of head is going to be hard to find in a submersable. And I still think you may have a heat problem with a submersable that big.

I wouldn't skimp on the pressure side. An eductor will cause a lot of head loss on its own (as compared to a straight outlet with the same diameter as the return pipe). So you need pressure to lose in the eductor itself (converting flow quantity into high flow velocity), so that you can effectively convert that velocity back into larger volume (at much lower velocity).

All that eductors do is convert momentum from low volume at high velocity to high volume at low velocity. But they incur a headloss (pressure drop, or waste of energy) in doing so. Great for when you are trying to get a high flow volume without blasting the flesh off your corals. Not so good if you don't have the pump capacity (pressure) to spare.

 

[reedman]

That's exactly it as Don described it. I figure I could use a smaller pump capable of high back pressure to generate a lot of flow. Since my sump will serve only one purpose (a place to put all that crap I don't want to see) I am not at all worried about how much flow gets through it. I am limited to about 600 gph on the high end due to my overflow limits.

If I can't find a submersible that can handle this I'll just go with an appropriate size return pump. No biggie. Just thought this would be a nice addition and a way to keep the size of the pump down.

Eliyah,
I'm all ready to go except for the return pump and the replumb of my closed loop. Quite excited to have a sump and a much bigger skimmer.

 

[les]

To get 10 psi out of a pump you will need one good for 24 feet of head per eductor. I looked at the Danner Mag drives and the Mag 36 is down to 50 GPH at 23 feet of head. That works out to 9.956 psi at 50 GPH. At a 10 to 1 ratio, thats alot of pump heat for 500 GPH. Good luck with finding one that will work for multi eductors.

By the way, to figure psi for a pump, look on the pump curve chart for the given head feet and divide by 2.31. Hope this helps.

 

[big t]

Good info les, I will have to try to remember that one.

Reed, that is exciting that you are finally getting your sump dude! Way to go. So what route did you end up going? In the basement, or under the stand? Also why do you want a submersable? They suck.

 

[reedman]

Thanks for the info les. I understand that it is very unlikely that this will work, but though maybe someone has checked it out already.

Hey Tom! Yeah, it's a long time overdue to have a sump setup on my tank. I'm going to have it next to the tank in a small cabinet (top will flip up for easy access to all contents. I am planning submersible because it is a glass sump and I don't want to drill it, I really don't have the room for another pump outside of the sump, and I really don't need a lot of flow through the sump, just enough to feed fresh water to the skimmer and return it to the tank. I already have the AM3K for flow, I just thought I might be able to take advantage of another source of flow without getting a big pump (another energy draw). I'll probably just go with a smaller mag based on the feedback here.

THANKS ALL! many minds are better than one...especially when the one is mine

 

[dnjan]

THANKS ALL! many minds are better than one...especially when the one is mine

You would have figured it out completely on your own if you would have had a hockey game on in the background!

 

[reedman]

You're probably right Don. This hockey thing is killing me.