I thought most people were using Mag 12's on the 24" which would put up about 11.8 ft of head at 250 gph. The recommended Mag 9.5 is only few inches less than the Mag 12. He does recommend the Mag 18 for the 30 and 36" models which will put up about 15.8 ft of head. You do need more head with the taller skimmers to overcome the backpressure on the backside of the injector.I’ve been part of that RC thread for quite some time. i remember the Dwyer airflow meter tests specifically as I had a Fluval SP4 on my 24” skimmer at the time and somebody put up the airflow numbers for the SP4 on both the 24 and 30 inch skimmers. IIRC, wasn’t it mentioned on that thread that Jeff used a Mag 12 or 18 on his 24 incher?
A 24-36v DC motors (kind used in this hobby) by themselves will never more more efficient than a 120V AC motor. Think about it. They take 120v power and have to step it down to 24/36v, as well as power the electronics to drive the motor. That stepdown always creates heat, which is wasted electricity. In fact, that is the reason most DC pump controllers fail. They are undersized without adequate heat sinks, so they get hot and fail prematurely. The difference comes in the fact that the DC pumps are typically designed to be high volume/low pressure pumps. Most of your Iwaki/Panworld or Sicce pumps are higher RPM with smaller impeller housings and smaller output sizes. They usually handle head pressure better, making them better for this application. Where DC pumps do outpace AC pumps is in the noise department. The controllers are able to smooth out the impulses. I wouldn't be too worried about pump power consumption in this range of application. Reason being that in a submersible pump, 99.9% of the electricity sent to the pump is converted to heat inside the water. So unless you run into heat problems and don't run heaters, any excess power consumed by the higher pressure pump, will be offset by running your heater less. Also, when you choke down the water flow at the injector, it actually lowers the power consumption. You would think it is opposite, but it isn't. Take a AC pump and put a valve on the outlet. As you restrict the flow on the outlet, the power consumption will go down. My advice is that if you can find an AC pump that you are comfortable with the noise level, use it. They will always be more reliable than their DC counterparts and in most cases, won't cost you a dime of electrical cost. IMHOInteresting, so why doe sthe AC pump pull so much more power? Is it actually more powerful? I am confused because he says the pump needs to be 600gph but told me a jebao 4500 (1056 gph) is not strong enough but his Mag drive (1010gph) is. I dont understand.
DCP-6500 on 30
Unfortunately I have to sell my 30 as it don’t fit under my new Waterbox
When I first got mine I used a Mag 18 and I know people don't like them for one reason or another but They do work very well. I dropped mine while cleaning it on day and replaced it with the DCP-6500 because a local shop had it on the shelfI use mag 24 (per Jeff’s recommendation for this lifereef skimmer (42”totalheight) fed from sump opposite side of wall . Does well for 3years now.
The Jebao pumps can certainly work, but the developed head drops off very quickly as the flow increases. The actual head of the 6500 flowing 300 gph through a Mazzei is only going to be about 11.5 ft - very similar to the Fluval SP4. The AC pump curves hold the head much better as you start increasing the flow.That works well for that size? Seems like it would be undersized.
Can someone explain how the fluval pumps head is low compared to watts and flow rate? Is jebao just drastically over stated?
Jebao 8000 states 18ft at 65 watts 2100gph, I am struggling to understand which pumps are best with these skimmers. It would seem jebao dcp is a no brainer but people suggest ac pumps such as sicce and fluval.