I really dislike mag drive pumps

Cory · Nov 3, 2016

Ive had many pumps over the years. Out of them all I absolutely dislike mag drive. Every time i turn them off they wont restart! How i get them going again is to stick a screw driver in the propeller to get it to turn. Not to mention they are so loud! And they heat the water so much and are huge energy consumers. I wish people would stop reccomending mag drives.

A lot of times mag drives are rebranded over and over. Sca-302 has a mag 5 on it and its the same problem, doesn't restart unless you give it a push.

My most favourite that ive tried as an in sump pump is the Eheim. Never cleaned it, had it more than two years, always restarts! Not only that its queit and consumes low power.

My next pump will be a little giant or iwaki. These pumps are reliable, if you want an external pump.

bif24701 · Nov 4, 2016

I would suggest a DC motor pump. Like the RO Varios line, well made, controllable, low power consumption, good flow, true slow start, and good price.

Cory · Nov 4, 2016

bif24701 said:
I would suggest a DC motor pump. Like the RO Varios line, well made, controllable, low power consumption, good flow, true slow start, and good price.

Talking about this?

http://m.marinedepot.com/products/cv25218/reef-octopus-varios-2-controllable-dc-circulation-pump

Start up every time?

bif24701 · Nov 4, 2016

Cory said:
Talking about this?

http://m.marinedepot.com/products/cv25218/reef-octopus-varios-2-controllable-dc-circulation-pump

Start up every time?

Exactly. There are also the larger -4 and -6 and soon a -8.

There is a recent thread that talks about DC pumps. It's a good one.

DC pumps have higher start up torque compared to AC pumps. So small things or a little build up that might stop an AC motor from starting up because they don't have a lot of torque at low speed (start up). DC pumps don't have that problem.

Drakonis · Nov 4, 2016

I love my iwaki main pump. although it does have some harmonic noise that needs isolated its easily mediated and that thing does nothing but run and i bought it used. i do have 2 mag pumps, one is my utility pump for transfers and such. the other is in constant duty to run flow to aux tanks in my sump system. it has been prety darn reliable for me but it does give off good amount of heat for a pump that doesnt bother my system as i run two heaters and the pump heat helps mediate the second heaters cycles. so over all yea they are probably best as a utility pump or if used for full duty know the ups and downs.

bif24701 · Nov 4, 2016

Also DC pumps are MUCH quieter!

Here, this should help. Take a look here, this guy explains the advantages and differences.

AC and DC pumps.... not as different as you may think.

https://www.reef2reef.com/index.php.....-not-as-different-as-you-may-think..271377/

steve&mari · Nov 4, 2016

I also dislike mag pumps and highly recommend dc pumps they got lots of advantages.

Drakonis · Nov 4, 2016

I dont know lifespan of these DC pumps but one thing to mention about fixed magnet motors is eventually the magnets weaken causing higher rpm and lower torque. so presuming the pump lives to that age it could loose enough torque flow rate falls off

mcarroll · Nov 4, 2016

Yeah I've never heard this complaint about Mag's.....if anything they are stronger starting than most AC pumps.

I'd guess that a Mag performing this way is either:

dirty/encrusted - likely after a little fun abuse. Vinegar and elbow grease are usually required in greater quantity than it first seems. Letting the pump completely dry out can expose hidden calcium deposits.
operating in a dirty environment - run a prefilter sponge if needed. I've reintroduced sediment to a freshly cleaned pump more than once by using a dirty/poorly cleaned sponge.
needs a new impeller - if anythng happened to the current one to weaken it, it will definitely affect performance, including startup. Dropping or heating such as during a dry run are two things than can de-power a magnet.

Ignorant American question: Are you on 50 Hz up there? I know that has an overall effect on pump performance.

Ditto on the thread @bif24701 mentioned, BTW!

bif24701 · Nov 4, 2016

Drakonis said:
I dont know lifespan of these DC pumps but one thing to mention about fixed magnet motors is eventually the magnets weaken causing higher rpm and lower torque. so presuming the pump lives to that age it could loose enough torque flow rate falls off

Do you have any data, article, or reference to go along with that? I have not heard that about permanent magnet brushless motors.

bif24701 · Nov 4, 2016

Drakonis said:
I love my iwaki main pump. although it does have some harmonic noise that needs isolated its easily mediated and that thing does nothing but run and i bought it used. i do have 2 mag pumps, one is my utility pump for transfers and such. the other is in constant duty to run flow to aux tanks in my sump system. it has been prety darn reliable for me but it does give off good amount of heat for a pump that doesnt bother my system as i run two heaters and the pump heat helps mediate the second heaters cycles. so over all yea they are probably best as a utility pump or if used for full duty know the ups and downs.

For pressure rated applications an external AC pump pressure pump is the only way to go as I am not aware of any DC pumps that are pressure rated.

If you don't need a pressure rated pump then DC is the way to go. They have advantage over AC in every way (other than what I mentioned before) with no real downside.

Quieter, cooler, more power efficient, true slow start, variable speed capable, high start up torque, controllable via APEX (some), remote power supply, more durable, can be used internal or external.

DC is better.

120reefkeeper · Nov 4, 2016

This is an interesting viewpoint. I've run mag drive pumps for years and years of faithful service. Now saying that , when I go to replace mine I'll be looking at the DC pumps. Not because I think they are better , but because of energy consumption and heat output.

The only thing I'll say about mag drives is that they are work horses! I keep a few impellers around for the rare times I need to change one. Dollar for dollar I believe they are a great value!

TheEngineer · Nov 4, 2016

I hated my mag pumps too. Poor restarting was an issue but more than anything is how inefficient they are. Thy are double the power draw of most comparable AC pumps.

Drakonis · Nov 4, 2016

bif24701 said:
Do you have any data, article, or reference to go along with that? I have not heard that about permanent magnet brushless motors.

I work with dc permanent magnet motors at work, happens all the time. typically the halfway mark fix is reducing the servo amplifiers startup torque as these are tracked by 2000 count encoders so to stop them from jerking and overshooting target movement we have to turn down the torque but eventually it gets bad enough the need replaced

Drakonis · Nov 4, 2016

bif24701 said:
For pressure rated applications an external AC pump pressure pump is the only way to go as I am not aware of any DC pumps that are pressure rated.

If you don't need a pressure rated pump then DC is the way to go. They have advantage over AC in every way (other than what I mentioned before) with no real downside.

Quieter, cooler, more power efficient, true slow start, variable speed capable, high start up torque, controllable via APEX (some), remote power supply, more durable, can be used internal or external.

DC is better.

I get your arguement for DC is better but i am a big fan of iwaki design, they have a rock solid reputation, and i only payed 40 bucks for a md40 lol so was no competition at that point.

MaiReef · Nov 4, 2016

My Sicce has been great and quieter than the mags, however I only had that problem with 1 mag out of 3. I actually am trying the Jebao DC pump. I have one on order.

Elegance Coral · Nov 4, 2016

There are some really old mag drive pumps still in operation. These are strong, reliable, pumps with a track record that's hard to beat.
They are not as energy efficient as some of the more modern pumps, that is surely true.
I work in the industry and have used many different types and brands of pumps. Not a big fan of the DC pumps. At least most of them. In my experience they simply don't have the reliability of the old school mag drives.
One example. We set up a 1200 gallon reef tank with all DC pumps. Two different brands. A year later, and all of them had been replaced due to failure. We've also had to replace countless DC skimmer pumps.
So far, we have had good luck with the newer Vectra pumps, but they haven't been out long enough to speak about longevity. They're also a little pricey.
I work alot with sicce pumps and have nothing bad to say. I've personally been running two PSK2500's for about a decade with no problems at all. Still running the original impellers.
IMHO, you can't go wrong with any of the old school pumps. Like mag drive, maxijet, little giant, Iwaki, and reeflo dart.......... There's a reason these are still around decades later. The only exception is quiet one pumps. These things are garbage but simply refuse to go away. LOL

Peace
EC

mcarroll · Nov 4, 2016

The more I read the more it sounds like the entire first generation of these DC pumps is already dead

But we still keep hearing about how much better they are – mis/dis-information and all.

It's a little baffling...but then fads usually are

Mike in CT · Nov 4, 2016

I have had 2 mag 9.5s going for 4 years straight. I have never had to touch them and have never had a problem with them restarting. They do throw off some heat, but that just means I don't have to use heaters, so I probably save any money that I would I would make up by using more efficient pumps. Just my experience.