pump ideas

[frag master flash]

I think sjm817 is correct. Running Mags thruough 1 inch plumbing and running the flow through other things such as reactors will sig cut down on flow. I changed out a mag 7 with slightly lower flow rate pressure rated pump and the difference was night and day - read flow like a fire hose. The one inch standpipe overflow could not keep up and I had to significantly throttle it back. I ended up getting a new pump rated at less than half of the mag and it gave me about the same flow. My return line was more restrictive as well (3/4"). Not saying that this is definately an issue, but you might be surprised by the increase in flow if you switch to something that handles pressure better. Were you using the Mags when you were running 3000 gal/hr through the sump?

[Lucky-rc]

Originally posted by frag master flash
I think sjm817 is correct. Running Mags thruough 1 inch plumbing and running the flow through other things such as reactors will sig cut down on flow. I changed out a mag 7 with slightly lower flow rate pressure rated pump and the difference was night and day - read flow like a fire hose. The one inch standpipe overflow could not keep up and I had to significantly throttle it back. I ended up getting a new pump rated at less than half of the mag and it gave me about the same flow. My return line was more restrictive as well (3/4"). Not saying that this is definately an issue, but you might be surprised by the increase in flow if you switch to something that handles pressure better. Were you using the Mags when you were running 3000 gal/hr through the sump?

Yes but back then I had a mag 36 and only one 18. They both were 1" but they went from the sump directly to the tank... No uv or other reaction chambers to slow them. I did this because it seemed like the detrius was floating around but just was not getting pulled to the overflow. When I increased the flow rate through the sump it was like everything was getting sucked right to the overflow then.

So let me ask you this.
An external pump lets say the dart has a head psi of 12 ft and 2500 gph @ 0 (don't remember the exact #'s)
Does this mean it will pump 2500 gph " UP TO" 12 ft. then decrease?

Assumeing you read this whole thread: Would the dart be ok? I am not really after more flow through the sump Just something that will run cooler and maybe even be a good "up-grade". But I do want to keep the same (at least) flow I'm getting from my mag's

Lucky

[frag master flash]

The manufacturer usually lists both the maximum head pressure and the maximum flow rate. The two are mutually exclusive. In order to better understand what you will get in your particular application, you would want to look at a flow chart that shows flow vs head pressure. You can find this info on the marine depot website (or google it as many other e-tailers have it available). My understanding is that this is the max flow you would get at these heights. Added 90 degree elbows, reactors, restrictive plumbing and other things will decrease the flow further. Sorry, but I have never personally used a dart, so I will have to leave it to someone else to tell you if it will work in your setup. It is a very popular pump and there are lots of people using them, so someone should be able to give you an answer.

[Lucky-rc]

ok. Thanks for the info. I'll see what M.Depot has listed.

Lucky

[sjm817]

A Mag36 with 1" plumbing is like putting a cork in it, even the Mag18 to a somewhat lesser degree. Mag pumps need big plumbing to get flow from them. Again, I'm not a high sump flow guy, and also dont understand how you have managed to run that much flow through a small sump unless it is somehow severely restricted (the 1" plumbing explains it somewhat). I wouldn't use a Dart, but it may work for you. Note that a Dart has a 2" inlet and a 1.5" outlet for a reason. Its a flow pump. To get those flow numbers, like a Mag, you need large plumbing. I would use the Tarpon.

[Lucky-rc]

well my sump is a "high flow" sump. built by Inovative Plastics. It was custom built to match the tank (310) high flow was the whole purpose when they built it. Because I told them it was going to be a fish only tank.
On the mag's they have a 3/4 neck so I didn't know 1" would hurt.
Also my stand tubes for the intakes are only 1". With the dart I assumed I would have to change all the lines. I also assume I'll have to change my stand tube as well. Is this correct?

Lucky

[Lucky-rc]

also I am sure that my measurements my be off. I came to this conclusion by looking at the little graph that shows gph per foot.
I had 2 90 degree elbows (one at each stand tube) but no other restrictions. But for couriosity the sump can handle it. I don't have any intentsion of pushing that much. I just want to see about 1 pump to replace the job of two. So if I have two mag 18's that with the elbows and feet to pump they should be getting 2000 gph thruogh the sump. So lets say due to the plumbing and the uv/carbon chamber I'm only getting 1,000 gph(50% reduction) This is fine I don't need more flow than I already have. The option to have more would be good. This would mean the the pump I select would not be working at max. As you had ststed before "saving electric and produceing less waste heat".
Lucky

[sjm817]

You are supposed to double the plumbing size on a Mag. I dont know why they put undersize fittings on them and expect people to double it. It creates a lot of confusion. Mags lose a lot of flow when head is added to them. A pressure rated pump does not.

[Lucky-rc]

ok now that makes sence. I could not understand before, because the mag will only let so much flow through the 3/4 neck.
I also now understand the difference between it and a psi pump.
your last post was very clear and well stated. Which leads me to believe your right about the Tarpon. With it would I be ok with my 1" stand pipes? or should I change them also?

Lucky