pump up your air pump!

[MCA]

I have posted this on KoiShack. I figured this might be of interest to those that do the Shack.




While designs for the different brands and models of diaphragm pumps vary some....they are all using the same principle. You have two large electromagnetics (looks like large transformers). Suspended between the electromagnets are two permanent magnets in a plastic frame. The plastic frame has a threaded rod on each end. These threaded rods are inserted into reenforced holes in the diaphragms. So when the the alternating 110V current makes the two eletromagnets change their field direction (ie north pole, south pole) 60 times a second, those permanent magnets react moving one way and then the other. This is what causes the diaphragms to move and act like bellows on a iron forge.

On the outside of the diaphrams are plastic end blocks. The contain the check valves and passages that direct the pumped air in one direction down to the underside of the pump. The check valves, just like the diaphragms, are made from synthetic rubber and definitely wear out. So if you see an air pump running with what looks like 50% output....it could be
one or more ruptured diaphrams (very likely)
or more more broke check valves (very likely)
one or more electromagnets have died (not so likely)

Depending on the brand and model of air pump. your purchase individual replace about parts or kits. Some kits contain a new fiilter. This is really needed...just wash and dry the old one. What you do need to have on hand is at least one set of diaphragms and check valves.

Check out this site... http://www.septicsolutions.net/store/homepage.htm

Why route you to a supply of septic tank systems? Because a septic tank, just like a koi pond, runs much better when there is plenty of air moving things about. Also look at all the brands they carry. Where did you see such a selection for a pond supply house?

Next go to the parts page: http://www.septicsolutions.net/store/PumpDifferences.htm

Select a brand and model of pump....lets try one of the HiBlow models http://www.septicsolutions.net/store/PumpDifferences.htm
Here you can see the end blocks and diaphrams.

On this page you can find Alita parts: http://www.septicsolutions.net/store/alitalinear.htm
Whe you scroll down....note you can purchase the check valves seperately!!!!


For a Medo linear piston pump: http://www.septicsolutions.net/store/medoairpump.htm


Clean the filters several times per year. Have spare diaphragms and check valves (or piston kit for Medo) on hand for all the different brands and models you use.



Yes.....some of the check valves and diaphrams just might fit another brand and model as well.



My point is with all this...... keep your air pumps working...your fish depend on them!

[KoiCop]

Michael . . .

That's a great link. Thanks for posting it.

[MikeM]

Question: What type/brand of air pump suitable for outdoor use with a koi pond is the most durable and efficient?

[MCA]

Well, in our little world of koi keeping...we don't have Consumer Reports testing of the components we use. Danged if would not be nice if we did have those!

I did a comparison of some pumps regarding the air they can deliver at several depths. This survey did NOT include all available brands. But it gives you an idea of which brands/models may fit your pond system needs.

For example...want to deliver 120L of air to a Nexus or other 1meter deep fluid bed....no problem. Most any brand's 120L models, will do the job...but using different amounts of power. But try to drive 80L to a diffuser dome at 8' deep. This is where you can see than the Medo line of piston pumps just can not deliver to high backpressure.

Remember you need to balance capital expediture (cost of the pump) with operating expediture (electricity plus replacement parts) and performance (air volume delivered at specific backpressure.

For our needs I use an Airtech 120 on each nexus and an Airtech 80 on each BD at 8'. Works for us. Our Airtechs sit outside in the filter pit.

[Lam Nguyen]

Very good info, MCA. I especially found the 'air pumps' attachment really helpful. I like the comparison chart of the different air pumps. I wonder how the Hi-blow brand of air pump compares to these models. Also, I assume that the 40L per 1200 gallons of pond water includes both the air that is used to aerate the pond and the air that is used to aerate the filtration system.

It would be nice if one of us could compile a list of the different brands and their advantages and disadvanges. We could also use comparison charts for the digital DO and ORP devices as well. This would really help those that are new to the hobby such as myself from wasting their time and effort in experimenting with different devices. Once again, very helpful thread. Thank you.

[MCA]

Very good info, MCA. I especially found the 'air pumps' attachment really helpful. I like the comparison chart of the different air pumps. I wonder how the Hi-blow brand of air pump compares to these models. Also, I assume that the 40L per 1200 gallons of pond water includes both the air that is used to aerate the pond and the air that is used to aerate the filtration system.

MCA: You can look up the specifications for HiBlow, Pondmaster (Danner), Hailea, or others and add them to your comparison. In the other thread there is a link to the Septic Solutions company that sell many brands. You will have to convert backpress in bars or psi into water depth in meters to make the comparison for air delivered at the same backpressure.


It would be nice if one of us could compile a list of the different brands and their advantages and disadvanges.

MCA: Other that capital cost (from which vendor on which day?), operational costs (stick to watts not dollars of electricity) and performance (liters at X meters).....what advantages or disadvantages should be noted?


We could also use comparison charts for the digital DO and ORP devices as well.

MCA: Don't know but of one ORP meter that can be calibrated by user that is afforable by hobbyist...PinPoint by American Marine. If there are others, that would be interesting to know.


This would really help those that are new to the hobby such as myself from wasting their time and effort in experimenting with different devices. Once again, very helpful thread. Thank you.


MCA: You are welcome.

[Steve E]

As part of the pond remodel I have plans on adding extra air to the bio chambers. Whilst running the plumbing I wondered about actual air flow due to friction loss in the piping as well as that due depth of water. Has anyone ever used an air flow guage to meter the amount of air flowing or to check how much air is actually flowing? AES sells a pitot tube type water flow meter and the company that makes that particular one has others that can meter air flows in the ranges that we like to use. Can not remember the name of the company right now and can not find where I filed the product information I downloaded. The ones I am talking about are the clear acrylic ones with flow measured from a pitot tube placed into the water line.

Steve

[MCA]

The pump vendors make performance charts that tell you how much air each model will deliver at a given backpressure (psi, meters of water depth, bar...etc.).

I use 1" pipe to deliver air to the air domes. Since is air is far more fluid than water, I know than all the backpressure on the pump is the 8' of water depth...not pipe restrictions.

Remember that any device that measures pressure...much add backpressure. Just like a voltmeter is actually mearuring current.

[KoiCop]

MCA . . .

Ordered a rebuild kit today from your septic site for our Medo 80 linear pump.

It's been in continuous use since 2004; output has dropped as compared to the other Medo 80 which is only a year old.

Will advise when/how the rebuild goes.

[MCA]

Don,

Keep us posted.

One thing neat about the Medo concept is that you add another piston for each 40L of air. So a rebuild kit for 40, 80 or 120 is 1, 2, or 3 sets of pistons, rings and springs. Much simpler and elegant idea than diaphragms.