Need advice for needle wheel pump for sump

[jart]

Hi all,

I'm planning a 6 foot 125 gallon tank. I'd like to have a sump... not sure how large it will be yet... thinking in the range of 30+ gallons.

I'd like to supply CO2 via a needle wheel pump, which will be situated in the sump. So the outflow of the needle wheel pump will go directly to the tank.

The pump I have in mind is the Danner model 18. I was wondering if anyone has an opinion on using this pump in the sump on this size tank.

Best regards.

[Gerryd]

Hi,

I use a mag18 on my 220 gal. I have a rio 1k NW pump in the sump. the NW output gets picked up by the main sump pump for in tank distribution. You should be fine. Give yourself a gate/ball valve to throttle flow if necessary.

[jart]

So why go with two pumps when arguably only one would do? I suspect your reasoning is that you believe the output from a needle wheel may be less than a non-needle wheel pump (I seem to recall you posting this before).

Thanks Gerry; I appreciate your input.

[Gerryd]

The NW pump is solely for c02. The mag 18 solely for driving the filtration. Easier to have spares/backups for each.

If the c02 pump goes at least the filter is still running.....

[Tom Barr]

CO2 mist is chopped up ultra fine also, less haze in the main tank.
A main return should not have a NW impeller, waste a lot of flow!!

The other thing you could do is put a larger water filter with clear housing, say a 4.5" x 20" and modified it like the Cerge CO2 reactor and use that instead. This would be post Mag 18 and used 1" in/out, so you can use that PVC size or reduce to 3/4" if you wish.
This should catch most of the CO2 or you could use as a traditional reactor. I might go this route to conserve and improve CO2 efficiency. I can easily switch back and forth and still leave the reactor in place also.

[mike]

Hi jart,

I use a mag 9.5 with NW and a mag 18. If you have a NW on your pump you will loose about half the rated flow. I did some test with my pumps. My 9.5 with NW gave me about 500gph with 18 inches of head and it gives me about 380gph with 5 feet of head. I only tested my 18 with 5 feet of head and it gives me 1100gph. I was originally feeding co2 right into the 9.5 but I found there was too much mist. What I do now is I have a Rio 600 with NW. I put a tee on the output and placed the Rio between the 2 return pumps with the tee pointing at each pump. The Rio does a good job chopping the bubbles and the two mag pumps disperse the co2 really well.

The only issue I have now is trying to get more oxygen into the tank. I can't seem to drive the co2 much higher than 30 ppm without causing some stress.

I'm going to put a video together of my overflow and returns.

Mike

[jart]

A main return should not have a NW impeller, waste a lot of flow!!

Really? I had no idea that this was the case until you and Gerry pointed this out. Thanks, you both have saved me a lot of time on this project.

The other thing you could do is put a larger water filter with clear housing, say a 4.5" x 20" and modified it like the Cerge CO2 reactor and use that instead. This would be post Mag 18 and used 1" in/out, so you can use that PVC size or reduce to 3/4" if you wish.
This should catch most of the CO2 or you could use as a traditional reactor. I might go this route to conserve and improve CO2 efficiency.

Which route? The Cerges or the traditional reactor? I was originally planning on two Cerges reactors with a canister... but the sump pimps have led me t'wards the light!

I can easily switch back and forth and still leave the reactor in place also.

Switch back and forth between what exactly?
(Sorry for all the questions...)

The NW pump is solely for c02. The mag 18 solely for driving the filtration. Easier to have spares/backups for each.
If the c02 pump goes at least the filter is still running.....

Good point. Thanks for your expertise. And thanks also for taking the time to post the sump video.

Hi jart,

I use a mag 9.5 with NW and a mag 18. If you have a NW on your pump you will loose about half the rated flow. I did some test with my pumps. My 9.5 with NW gave me about 500gph with 18 inches of head and it gives me about 380gph with 5 feet of head. I only tested my 18 with 5 feet of head and it gives me 1100gph. I was originally feeding co2 right into the 9.5 but I found there was too much mist. What I do now is I have a Rio 600 with NW. I put a tee on the output and placed the Rio between the 2 return pumps with the tee pointing at each pump. The Rio does a good job chopping the bubbles and the two mag pumps disperse the co2 really well.

Thanks for the info.

What size is your tank? That will help me decide what model needle wheel pump and return pump to get (if I decide to go this route, as opposed to a return pump and rector as suggested by Tom.
Are you pleased with your set up, Mike?

I don't mind a bit of mist
I really don't think I'm going to push the upper limits of CO2 in this tank... hopefully lower light will prevail . No time to trim with a newborn in the house...

I'm going to put a video together of my overflow and returns.

Please do! That would be most helpful.