return pump dead after 1 month (mag7) return question too

[Conceyted]

Alright I get home from work tongiht and see the tank is extremely quiet. I look at the chiller and its reading 70 degrees. I am wondering what is going on. I look at the tank, the water level is about a half inch below the trim. Something obviously isnt right. I put my reefkeeper on standby and then back off again, no action. I take a look in the sump and realize whats up. My brand new (2 months old) mag 7 has stopped pumping. My return is pretty simple, if you would like to find pics of it click on my red house. I took the mag out of the sump after unplugging it and upon disassembling it and removing the impeller I found the impeller to be extremely hot to the touch. The entire pump housing was also warm. I let it cool off and tried starting it up again, nothing. All you can hear is a slight hum coming from the pump housing. The impeller isnt turning, the magnet drive isnt moving. The thing is DEAD. I am really ****ed off now, but as the same time I am glad I found it before I went to bed. A day without a chiller would have meant death to my sps. I hooked up a mag3 temporarily untill I can get a new pump. I am thinking of sending in the mag7 for replacement since its under warranty but i am also thinking of just trashing it and buying an eheim.

I have one question however. With the eheim it claims to have a 3/4" outlet. My return is plumbed with 1/2" pvc and I am wondering if I could keep the 1/2" pvc plumbing and just use a reducing coupler at the pumps output to hook it up to the return. Once I get this out of the way its smooth sailing.

FWIW my mag3 has been running or over a year with no problems. This is the first problem (besides bringing the tank temp up 2 degrees from running hot) I have ever had with mag pumps. But after something happening like this so soon I wont be buying another one.

[sumpinhabitant]

If you bought it new they will replace it for you. IMO this is just a freak occourance i've used mags for years and never had a problem.

[mg426]

Get it replaced under warrenty. I have never had a problem with mag pumps. I have a Mag 7 that has been running 3 yrs straight.
Never had a problem.

[Mekong]

Odd I have used many mags 3-9.5 with no probs

[chip721]

I've had a Mag pump seize on me before. But mine was due to lack of maintenace on my part. I took it apart, inspected it and it had simply got over calcified. Gave it a good vinegar bath and it was fine. But you shouldn't be having that type of problem with a 2 month old pump. I'd also be contacting the vendor expecting a replacement.

[RichConley]

Originally posted by Conceyted


I have one question however. With the eheim it claims to have a 3/4" outlet. My return is plumbed with 1/2" pvc and I am wondering if I could keep the 1/2" pvc plumbing and just use a reducing coupler at the pumps output to hook it up to the return. Once I get this out of the way its smooth sailing.

You're running a mag7 on 1/2" plumbing, as a return? No wonder it seized up on you.

I'd say 1" is ABSOLUTE minimum for these things, with 1 1/4 being more reasonable.

[Conceyted]

umm are you sure? why does the outlet have 1/2" threads then?

[jn79vette]

my mag 7 did the same thing.turns out my impeller shaft snapped.got a shaft from the lfs and it been working great ever since.

[Conceyted]

this isn't the impeller shaft though. that is all intact.

[RichConley]

Originally posted by Conceyted
umm are you sure? why does the outlet have 1/2" threads then?

The manufacturer reccomends that you use pipe twice the size of the output threads.

With that narrow pipe, and running it as a return, the pump was probably running near its shutoff head, and was just sitting there spinning, not really moving any water. These pumps are water cooled. If theyre running and not movign water, they burn out.

[Conceyted]

hmm so if I got the eheim 1260 with 3/4inch threads I need to run over an inch return? I shouldn't run 3/4 inch pvc

[RichConley]

I dont use eheims, so I dont know. Bigger pipe is always better though.

Danner specifically reccomends doubling the outlet size for their mag pumps.


I run a mag5 return on one of my tanks, through 1.5"

[sjm817]

Eheims handle headloss a lot better than Mags. I found that 3/4" Vs 1" made very little if any difference on my Eheim 1260. A Mag7 should have at a bare minimum, 3/4", preferably 1" (2x output). I would not run 1/2" on either of them.

[bklynmet]

Been running several different size mags nearly two years with minimal maintenance (once a year vinegar bath). It's odd that yours quit after 2 months. The 1/2 plumbing coulb be the reason.