Mag pumps

[Tom Richardson]

I would like any feedback regarding recommendations of mag pumps. I have been using 1.5 hp pumps for our oxygen systems but in some applications it's too much.I would like to offer a system using a one quarter hp pump (3-400 watts)

[TCLynx]

I don't like to use any pumps that use more than 300 watts for my systems!!!!!! I use an energy efficient pump for my large system and I think it would probably come up to perhaps 1/6th HP and it's easily supporting a fairly heavily stocked 700 gallon tank of channel Catfish.

For my smaller systems I've been able to run on pumps between 25 and 150 watts depending on the system.

I've so far found the Quiet One pumps to be very energy efficient for flow rates 30 gpm and below. I've only been using them for a few months but they have been good so far.

[David Hart]

Hi Tom, This isn't exactly the 'answer' you were looking for, but a little food for thought.....
Lets see if my 'madness' makes sense.....
I use smaller pumps...2 or 3 at a time....for 'redundancy'. If they can be plugged in on different circuits, even better.
Here's another thought...
Some system's oxygen level drops at night, usually due to algae....have that 3rd pump on a timer, runs only while it's dark. Lots of extra oxygen being added....especially, if it's feeding a venturi.
Plus, TC just mentioned, that she noticed the efficiency being higher in the smaller pumps.( at least in the Quite one's brand) It's worth the time, studying the 'performance curve' charts and the watts being used.

[TCLynx]

Well, I won't actually claim that the smaller pumps are really any more efficient, everything must be in scale to really measure such things accurately. (please everyone remember that I usually up size plumbing and have been able to operate things like Aquaponics Indexing valves on rather small pumps by careful system layout and large plumbing from the pump to the valve) Anyway, the Quiet One pumps seem to be very energy efficient within their flow rate range, part of this might be that they use larger openings and plumbing connections than many of their nearest flow rate/watt use competitors.

David Hart said:

Plus, TC just mentioned, that she noticed the efficiency being higher in the smaller pumps.( at least in the Quite one's brand) It's worth the time, studying the 'performance curve' charts and the watts being used.

From a pure energy efficiency/flow rate/aeration point of view, I doubt that several small pumps really add up to be the best value. However, David's point about having several small pumps on separate circuits does provide some protection and redundancy which can be a good thing. Better yet might be a battery or generator backup.

[David Hart]

'Sorry' TC, I should of been more careful, with how I mentioned you pointing out that smaller pumps 'may be' more efficient. I was trying to tie together, what you mentioned and how important it was, to really study the 'performance curves'.

I'll use the Quite ones' performance chart to make a point.......

The 4000 uses 50 Watts ....and at 0 head, produces aprox 15 GPM
The 5000 uses 110 watts.... .and at 0 head, produces aprox 19 GPM

In this case, using 2 -4000's would use less power, deliver a lot more GPM. Plus the cost (where I was looking at the charts)...the 5000 was aprox 40% more in cost, so buying 2 - 4000 wouldn't be too much more then buying 1 -5000
Too bad, the chart I was looking at....didn't show the figures for the bigger Quite one pumps. I wanted to see what the figures were, on a pump that would equal the (GPM's) performance of 2 -4000's

Of course this is just numbers on paper....lots of variables in the 'real world',

TC made a great point on over sizng the pipes.

Since pvc pipe in sizes under 1 1/2 inch do not (normally) come in long radius fittings, I go to the 'extreme' of using 2 -45 degree fittings together, instead of a 90. It does make a small difference. If done several times on a given run.....it adds up.

[TCLynx]

Yes, If working with a set up that has minimal head or pressure needs, the small mag drive pumps are more energy efficient.

However, many set ups need certain amount of flow at a higher head or they need pressure to run some types of filters or for injecting oxygen or aeration into water under pressure. In those cases the pump specs are going to be far more important since flow rate at 0 head means little to them.

[TCLynx]

Don't get me wrong David, your points are good. Just trying to expand on them and add points that probably pertain to more specific situations that the original poster might be looking at.

TCLynx said:

Yes, If working with a set up that has minimal head or pressure needs, the small mag drive pumps are more energy efficient.

However, many set ups need certain amount of flow at a higher head or they need pressure to run some types of filters or for injecting oxygen or aeration into water under pressure. In those cases the pump specs are going to be far more important since flow rate at 0 head means little to them.

[David Hart]

Thanks TC,
As usual, you make make lots of great points too.
Yes....The more points and variables, we can point out, the better choices, others may make in their choice.

Thanks for adding so much info and advice to the differant postings TC !

TCLynx said:

Don't get me wrong David, your points are good. Just trying to expand on them and add points that probably pertain to more specific situations that the original poster might be looking at.

TCLynx said:

Yes, If working with a set up that has minimal head or pressure needs, the small mag drive pumps are more energy efficient.

However, many set ups need certain amount of flow at a higher head or they need pressure to run some types of filters or for injecting oxygen or aeration into water under pressure. In those cases the pump specs are going to be far more important since flow rate at 0 head means little to them.

[Rob Torcellini]

I work for Iwaki America, which manufacture mag drive pumps. (I have nothing to do with sales....just run the IT department.) These are high-end pumps that are used for various applications like fuel-cell cooling, chemical pumping, waste water, and aquariums. (I believe most of the pumps used in the fish departments at Walmart are made by us.)

I've used a few "demo" units for some of my projects and are happy with them. They're quiet and efficient. However they aren't cheap! We also don't sell direct so they have to purchase them through a distributor. I know they're very popular with some of the aquarium folks because they are so quiet and never die. The are all external pumps, no submersibles.

With that said, I don't use them in my setup. I buy the cheap submersibles from Harbor Freight. ;-)

[Tom Richardson]

Thank you all for this discussion, our Gaia system currently uses a 11/4" in/out with the 1.5 hp pump (Waterways).
It has a head of about 3' . We need at least a 1' head to sufficiently push the water at enough speed through our patented valve so we can micro diffuse oxygen in water (our system keeps the oxygen as a gas in water which makes the oxygen saturation last for extended periods). There are no bubbles with our process. I will purchase a 1/4 hp pump, probably a 'quiet one' brand to test and will post my observations. I am hoping eventually through testing, to find a 1/6 hp pump with a 500 watt or less draw to work. Currently our system using 1.5 hp pump (80 gpm) uses 16 amps which is tripping breakers at open net salmon farms (electric generators). For open net salmon farms we are looking to produce a Gaia system at 2,000 gpm with a 20' head. Because these farms have over 500,000 salmon at about 5 lbs each, we need to oxygenate a lot of water. The pump will be submersible with a direct hookup to a dedicated diesel generator. Currently our 1.5 hp Gaia systems are perfect for large hatcheries and greenhouses. The 1/4 hp should be great for aquaponics. Please keep the discussions going, I am learning a lot and will share whatever I can as things proceed. Thanks!
Tom Richardson

David Hart said:

Thanks TC,
As usual, you make make lots of great points too.
Yes....The more points and variables, we can point out, the better choices, others may make in their choice.

Thanks for adding so much info and advice to the differant postings TC !

TCLynx said:

Don't get me wrong David, your points are good. Just trying to expand on them and add points that probably pertain to more specific situations that the original poster might be looking at.

TCLynx said:

Yes, If working with a set up that has minimal head or pressure needs, the small mag drive pumps are more energy efficient.

However, many set ups need certain amount of flow at a higher head or they need pressure to run some types of filters or for injecting oxygen or aeration into water under pressure. In those cases the pump specs are going to be far more important since flow rate at 0 head means little to them.

[TCLynx]

My main system pump (Sweetwater SHE 2.4) is not a mag drive or submersible but it does offer good energy efficiency. It uses under 300 watts when running and spikes at under 5 amps on start up. I would estimate it at about 1/6 HP since the info about it doesn't give a HP rating. At 5' of head the curve says it gives more than 60 gpm.

The next size up of that line also has a wattage of under 300 at 10' head and it provides over 80 gpm at 5'.
The next size down probably would have been sufficient for my large system but I'm happy to have the extra flow to try extra things.

Is there a specific reason to want mag drive or submersible?

[Michael sanders]

Rob,

I am looking for a way to monitor my system and I saw your video. Can I get some information on what products you used?



Rob Torcellini said:

I work for Iwaki America, which manufacture mag drive pumps. (I have nothing to do with sales....just run the IT department.) These are high-end pumps that are used for various applications like fuel-cell cooling, chemical pumping, waste water, and aquariums. (I believe most of the pumps used in the fish departments at Walmart are made by us.)

I've used a few "demo" units for some of my projects and are happy with them. They're quiet and efficient. However they aren't cheap! We also don't sell direct so they have to purchase them through a distributor. I know they're very popular with some of the aquarium folks because they are so quiet and never die. The are all external pumps, no submersibles.

With that said, I don't use them in my setup. I buy the cheap submersibles from Harbor Freight. ;-)

[Tom Richardson]

Is there a specific reason to want mag drive or submersible?
Mag drive pumps are oil-less. If you break a seal in a typical centrifugal pump, the oil could kill fish and plants. Once oil get into a system it is very difficult to get out. Cheers, Tom