Penductors: should I try them?

[funkyrxman]

So I’m in the process of switching out my return pump, and I’m thinking of adding penductors to my returns. So my new pump lists max head 37 ft. I guess I need to calculate my head pressure, but I think I might be good. New pump > 6000 gph. My returns are 7 ft above the pump, but 37 ft max head sounds like a lot right? So I’ve got the return split into 4 half inch locline returns. Wouldn’t I have to put penductors on all the returns? Otherwise wouldn’t the flow just favor the less restrictive returns? Would it be a bad idea to put a penductor on the return that comes off of the UV sterilizer? Would the pressure increase be bad for the UV? Maybe just 2 penductors on the ends? Tank is big, I can always use the flow. What do you think?

 

[P-Dub]

How big is the tank? What is the total volume? What is the actual output of your return pump? I would buy 1 or two and see what happens. The flow would likely favor the less restrictive returns but you should still see some benefit over not having them and likely, so long as your pump is rated for the pressure and it certainly seems it is, significantly more volume of water moving than the less restrictive outputs. Regarding a penductor on the UV, so long as the unit itself can handle whatever increase in pressure there is, it shouldn't be a problem. Ak=sk the manufacturer what pressure the unit is rated to or see if it is stated on the box or manual. The next step would be to guess the pressure output of your plumbing. Easier said than done. Perhaps someone has an idea to easily accomplish that measurement...

 

[funkyrxman]

How big is the tank? What is the total volume? What is the actual output of your return pump? I would buy 1 or two and see what happens. The flow would likely favor the less restrictive returns but you should still see some benefit over not having them and likely, so long as your pump is rated for the pressure and it certainly seems it is, significantly more volume of water moving than the less restrictive outputs. Regarding a penductor on the UV, so long as the unit itself can handle whatever increase in pressure there is, it shouldn't be a problem. Ak=sk the manufacturer what pressure the unit is rated to or see if it is stated on the box or manual. The next step would be to guess the pressure output of your plumbing. Easier said than done. Perhaps someone has an idea to easily accomplish that measurement...

Hey. Thanks for answering. Display tank is 450g, sump 60g. Pump is rated 6060 gph. Good idea on the pressure rating of the UV. I think I might try it after some more research.

 

[P-Dub]

Nice big tank! I'd get them. I have two that will be running on my 125 off a 6s for lots of flow along with 2 Icecap 3k's and 2 jebao RW40's. More flow in the DT is better for SPS's so...

 

[rockskimmerflow]

Yeah do it. I just set up a grow system with 7'x3' raceways. Running 1 eductor on each return (1 per tank) and each with its own panworld pump. Little did I realize that I could have gotten away with a single panworld 100px-x per 2 eductors rather than 1 pump per nozzle. They are monstrously powerful when combined with a pressure pump. Each tank is running in a nice strong circular gyre with that single eductor on the return input, more flow than I need for sps when I have the pumps opened all the way up.

I might leave the eductor off the UV line to be safe in your case, but I would say there is no issue with having only 1 or 2 nozzles running eductors out of the 4 since your pump definitely has the pressure to drive them. The pump will have plenty of extra flow to push the eductors even with 1 or more other inputs left unrestricted.

Always wondered about eductors but I think with the return of the hobby to simple laminar gyre flow they might make a comeback. I've always employed gyres using strong powerheads placed to create a circular current continously, but I never thought that a small funky looking nozzle would have the guts to move a whole tank sufficiently when paired with even a relatively modest pump. One of my trays runs on a panworld 50px-x which even at wide open only consumes 78 watts due to the eductors simulated head pressure on the pump. And it has more than enough flow to drive a 7'x3' raceway. I'm a believer for sure after having finally given them a serious try.

 

[jda]

What kind of pump is it? It will matter.

If you have a high flow, high pressure pump, an eductor can move further massive amounts of water. If you have a flow pump, even at high GPH, then they will not work as well.

Something on the extreme end like an Iwaki/PanWorld/GenX can see 5x the increase in water movement with 1000gph whereas a 1000gph DC pump would barely see any more.

I know that you did not ask, but with a 14' build coming up, I have been looking for flow pumps as well and EcoDrift 20.1 from AquaMedic move more water than anything else on the market, IMO... until somebody comes out with a larger Gyre.

 

[funkyrxman]

What kind of pump is it? It will matter.

If you have a high flow, high pressure pump, an eductor can move further massive amounts of water. If you have a flow pump, even at high GPH, then they will not work as well.

Something on the extreme end like an Iwaki/PanWorld/GenX can see 5x the increase in water movement with 1000gph whereas a 1000gph DC pump would barely see any more.

I know that you did not ask, but with a 14' build coming up, I have been looking for flow pumps as well and EcoDrift 20.1 from AquaMedic move more water than anything else on the market, IMO... until somebody comes out with a larger Gyre.

Thanks for the input everyone. The pump is an Abyzz A400. Your upcoming build sounds great. 14’ ! That’s a monster!

 

[rockskimmerflow]

What kind of pump is it? It will matter.

If you have a high flow, high pressure pump, an eductor can move further massive amounts of water. If you have a flow pump, even at high GPH, then they will not work as well.

Something on the extreme end like an Iwaki/PanWorld/GenX can see 5x the increase in water movement with 1000gph whereas a 1000gph DC pump would barely see any more.

I know that you did not ask, but with a 14' build coming up, I have been looking for flow pumps as well and EcoDrift 20.1 from AquaMedic move more water than anything else on the market, IMO... until somebody comes out with a larger Gyre.

Having seen the eductors in action on even more modest pressure rated pumps such as the 'flow' x-x panworld series I am convinced that the aquarium branded eductors do work well even with less than high pressure systems. A jebao DC is probably one I would leave off the list of pumps to use with an eductor, but things like that laguna/fluval sp series can definitely drive them. Just added a pair to the returns of an SP6 in a client tank and we were able to eliminate one of his 6105 tunzes and still had more flow than before.

 

[jda]

I consider a Laguna, Mag or Fluval a pressure pump as long as it is not maxed out at head, or something. SP6 with 5' foot of head is no joke.

 

[Larry L]

So I’ve got the return split into 4 half inch locline returns. Wouldn’t I have to put penductors on all the returns? Otherwise wouldn’t the flow just favor the less restrictive returns?

Not sure how you've got the returns plumbed, but if possible you should think about putting a ball valve on each line so you can tune the flow relative to each other.

 

[rockskimmerflow]

I consider a Laguna, Mag or Fluval a pressure pump as long as it is not maxed out at head, or something. SP6 with 5' foot of head is no joke.

Yeah it certainly is no joke. The SP6 with 2 eductors dropped a bit in overall sump turnover from the nozzle restrictions, but it really doesn't seem to have any trouble producing enough pressure to crank a lot of in-tank flow. To me Askoll motor pumps have always seemed to be 'flow' pumps rather than pressure types since their efficient operating range starts at pretty much 0' of head. Yes, of course they can handle decent head pressure, but that does not at all seem to be their design intent - moreso just a benefit of very efficient impeller and volute designs coupled with a extremely dialed in reluctance motor design. Whereas an Iwaki RLT or panworld PS series pump are what I generally view as by design pressure pumps since their efficiency range really doesn't start until you saddle them with more than 15' of head pressure or so. It'd be very electrically inefficient to employ one of those pumps in an application where they aren't seeing a real or simulated head pressure of 18-20'. I do love me a pressure pump, but I'm finding now with trying eductors in more and more tanks that any pump which can push at least 12' of head can realistically drive an eductor or two quite handily.