danner mag 3,4,5 or 7 for me?

[yzzuf]

well my damn eheim 1250 died after only 3 months of operation so its time for a new pump. at a local store here they offer danner mag pumps. im not so sure on whcih model to get. i need high flow because i currently have an rbx waterblock, dangerden gpu block and two 71 capri heatercores. also i have more tubing length than normal as i have this all in a huge cube server case so probably about 10-15 feet of tubing. i was thinking the model 3 because itys not as much watts, but the other modles are much more powerful and not much more money but they use more watts. what whould be a good choice here men?

[nikhsub1]

The ehiem died? That is a very rare event! Anyway, the mag3 would be good, better than the mag 5 but I dont know about the specs for the higher models. Since you have some serious rad-age, pump heat should matter little IMO. Why not go for an Iwaki or such? How much is the budget?

[seamadan000]

A mag 3 should do it, but if you want a bit more, the mag 7 would be a good choice as well. It has a head rating of 13', which is very comparable to the Iwaki WMD-20RT or the WMD-30RXT, two of the cheaper and more commonly used Iwaki pumps (if I am not mistaken). And the mag 7 pushes 700 GPM max, where the Iwaki WMD-20RT pushes 500 GPM. The mag 7 is also half the price, and danner pumps are very reliable (but then again, so are ehiems, you are kinda unlucky). So I would go with the readily availible mags, but if you want to really go crazy you could get an Iwaki

[yzzuf]

iwaki arent available to me locally and i cant wait days to wait for a pump to come from elsewhere as i need my comp asap. the only reason i was worried about the higher modles is that they put more heat in the water, but i also have two huge rads so.

[Froz]

Is there something wrong with the mag 5?

[Korndog]

Originally posted by Froz
Is there something wrong with the mag 5?
both the mag 3 and mag 5 have the same head, but the mag 5 has higher flow and it puts out a little more heat into the water then the mag3. In a restrictive setup, the extra flow wouldn't show much so basicly it'll be a waste of money and/or extra heat to ur system.

[Froz]

I thought in a restrictive setup you'd want a higher flow pump to overcome the restriction? Am I missing something obvious?

Thanks,
Froz

[seamadan000]

head overcomes the restriction, not flow, and a higher head rating pump will flow more water in a higher restriction setup, b/c the flow drop with restriction is not as high.

[pauldenton]

a mag3 pumps more than a mag5 above 6' of head.....which includes almost any w/c system (since at 6' they're still pumping 3gpm!)
the extra wattage is a side issue.
see here (just over half way down...)
http://www.aquatictech.com/pumps.html

[rmonster]

Originally posted by yzzuf
well my damn eheim 1250 died after only 3 months of operation so its time for a new pump. at a local store here they offer danner mag pumps. im not so sure on whcih model to get. i need high flow because i currently have an rbx waterblock, dangerden gpu block and two 71 capri heatercores. also i have more tubing length than normal as i have this all in a huge cube server case so probably about 10-15 feet of tubing. i was thinking the model 3 because itys not as much watts, but the other modles are much more powerful and not much more money but they use more watts. what whould be a good choice here men?

And here comes Koolaid! Not that I'm any kind of expert, but your current setup is very similar to my own:

Two capri-type (fedco 2-198, iirc) heatercores in parallel, in an external enclosure, with a Cascade (thanks Cathar!) cpu block, and a D-tek gpu block. I'm running around 14' of 1/2 ID tubing, and have run it with both a Danner MD3 and a Danner MD7, I still own both pumps and have swapped them out on the rig with no other changes several times.

There is no noticable difference in performance between the two pumps on my setup that I'm able to discern. My guess is that the extra flowrate of the md7 is offset by the increase in wattage in my case, but that may well not apply to different configurations.

Since your setup sounds very close to my own, I see no reason to spend extra money for a part that will yield little appreciable improvement (if any) over the md3. If I had to purchase a new pump for my system today, that would be my pick.