DIY 12v aerator

[Keyboard]

has anybody built their own aerator? air pumps on ebay are only about $10-15. im thinking along the lines of a 12 volt car battery to power it, and a solar charger to keep the battery charged.

looking for advice from anybody that might have done something like this.

 

[brokensword]

how much does a 12v car battery cost again? And the solar panel is how many $$ ? Don't forget the waterproof battery housing...ah, I'm thinking 10-15 dollars is looking pretty good!

 

[Keyboard]

how much does a 12v car battery cost again? And the solar panel is how many $$ ? Don't forget the waterproof battery housing...ah, I'm thinking 10-15 dollars is looking pretty good!

sure, its cheaper, but that isnt what i’m asking about.

 

[jmajid]

I have not made any yet.. but been toying with the idea.
Your setup is probably about right, you could use a car battery, but it would not last that long... you really need a deep cycle battery.
Those are meant to be discharged/charged many times.
You can look on Amazon for solar air pumps, essentially they come as a cheap-ish system with solar panel and air pump.
I know they have them... i did look at those, but have not bought one yet either, but it's on my list.
The other place i do research like this is YouTube - good for stuff like this...

 

[poconojoe]

How difficult would it really be to supply house current near your pond? Once installed, you're done. No dealing with chargers, batteries, etc. Plus, you'll be able to use a variety of devices that are much more reliable and functional. Pumps, aerators, lights etc.
The higher the voltage, the less current you will draw.

I don't know if this is basically just an experiment.

Just because it's only 12 volts, don't take it for granted. Lead acid batteries can be dangerous if you're not careful.

Yes, a deep cycle battery is what you'll need. The last deep cycle battery I bought was just under $100 and that was quite a few years ago.

I question how long that pump will run on a single charge.

Will the solar charger completely charge the battery every day? If not, that battery won't last long. It needs to be fully charged before putting a load back on it. It needs to be recharged immediately after it has been discharged.

How long is that inexpensive aerator going to last and will it produce enough air? For $10-$15, I doubt it will be adequate.

Go for it if you're really set on doing it, but you may be wasting time and money that you could have put toward installing electrical outlets.

 

[jmajid]

i second what @poconojoe said... however, for my need (once in a hundred years or just like Feb 2021), i want to be able to provide aeration in the event i lose electrical power for more than a day. Just a backup thing... not for my every day needs.

 

[Keyboard]

How difficult would it really be to supply house current near your pond? Once installed, you're done. No dealing with chargers, batteries, etc. Plus, you'll be able to use a variety of devices that are much more reliable and functional. Pumps, aerators, lights etc.
The higher the voltage, the less current you will draw.

I don't know if this is basically just an experiment.

Just because it's only 12 volts, don't take it for granted. Lead acid batteries can be dangerous if you're not careful.

Yes, a deep cycle battery is what you'll need. The last deep cycle battery I bought was just under $100 and that was quite a few years ago.

I question how long that pump will run on a single charge.

Will the solar charger completely charge the battery every day? If not, that battery won't last long. It needs to be fully charged before putting a load back on it. It needs to be recharged immediately after it has been discharged.

How long is that inexpensive aerator going to last and will it produce enough air? For $10-$15, I doubt it will be adequate.

Go for it if you're really set on doing it, but you may be wasting time and money that you could have put toward installing electrical outlets.

thanks for the tip on the deep cycle battery. that could be a deal breaker. the cost is no problem, but I wasn’t aware of the intricacies of the charge/discharge cycle. (it raises the question in my mind as to how well the little prepackaged kits with battery backup will work.)

im starting with a very small wildlife pond, and it’s a trial run for me. i have a backhoe and could bring in electrical power, but there are many reasons that I don’t want to, at least not initially. i may be back to square one - get a small solar powered unit that runs during the day and adapt to whatever shortcomings it presents.

 

[poconojoe]

i second what @poconojoe said... however, for my need (once in a hundred years or just like Feb 2021), i want to be able to provide aeration in the event i lose electrical power for more than a day. Just a backup thing... not for my every day needs.

It should be feasible as a backup. That makes sense.

When I moved into my neighborhood back in 1996, it was common to lose power, unfortunately.
I bought a portable generator for that very purpose. I used it more than a few times. Things must have improved since we haven't had to use it in quite a while, but we still have it... just in case.

You might be able to buy a very small generator for a little more than you might be paying for all that solar stuff. And you can power a few essential items in your home at the same time.

There are many street vendors that use those small Honda generators. They can't be too expensive.
You just have to watch your load (wattage). You wouldn't want to overload it.

 

[Keyboard]

How difficult would it really be to supply house current near your pond? Once installed, you're done. No dealing with chargers, batteries, etc. Plus, you'll be able to use a variety of devices that are much more reliable and functional. Pumps, aerators, lights etc.
The higher the voltage, the less current you will draw.

I don't know if this is basically just an experiment.

Just because it's only 12 volts, don't take it for granted. Lead acid batteries can be dangerous if you're not careful.

Yes, a deep cycle battery is what you'll need. The last deep cycle battery I bought was just under $100 and that was quite a few years ago.

I question how long that pump will run on a single charge.

Will the solar charger completely charge the battery every day? If not, that battery won't last long. It needs to be fully charged before putting a load back on it. It needs to be recharged immediately after it has been discharged.

How long is that inexpensive aerator going to last and will it produce enough air? For $10-$15, I doubt it will be adequate.

Go for it if you're really set on doing it, but you may be wasting time and money that you could have put toward installing electrical outlets.

 

[Keyboard]

thanks all for the input. im giving up the chase on this idea. it gets more complicated than i thought. I am still restricted to solar, but not diy. my next approach will be to adapt to the limitations of solar without battery backup.

I started a different thread looking for commercial recommendations.

 

[poconojoe]

thanks all for the input. im giving up the chase on this idea. it gets more complicated than i thought. I am still restricted to solar, but not diy. my next approach will be to adapt to the limitations of solar without battery backup.

I started a different thread looking for commercial recommendations.

That's one of the problems with going solar. You need batteries to store and provide the electricity.
It's not just a matter of "battery backup". It won't work without batteries.

 

[Keyboard]

That's one of the problems with going solar. You need batteries to store and provide the electricity.
It's not just a matter of "battery backup". It won't work without batteries.

it will work when the sun is out, and like I mentioned above, I can adapt to the limitations. no goldfish, no koi, maybe a few minnows for mosquito control...

 

[GBBUDD]

Those are meant to be discharged/charged many times.

[/QUOTE]
Not as many times as you may think constantly replacing boat and camper

 

[mgmine]

How much good will a small air pump do? If you have an aquarium size point then it will do a lot of good. If you have a bathtub size pond not so much good and if you have a larger pond no good at all. It will keep the ice off for a while in spots but that isn't what you are trying to do. If you don't have a regular pump at your pond then you will have stagnant water and a smelly mess.

 

[Solar guy]

You have to know what the watts required by the aerator is to determine the rest of the system. If you don't know that the rest is just guesswork and hit or miss. I know it all sounds confusing but it's really not that bad. i apologize up front if I get too wordy but that's just how I am.

Aerators generate about 1 liter of air per minute, or about 15.8 gallons per hour per watt.
So a 20 watt aerator would pump about 317 gallons of air per hour.

I'm just guessing, but I suppose a gallon of air would be equal to pumping a gallon of water per hour so if you use the guidance usually stated on this forum to pump a volume equal to your pond per hour, that 20 watt air pump should aerate a 300 gallon pond. I checked and found this size pump on Amazon for about $35 with an air stone and some hose.

Now, for the part I do know what I'm talking about, solar power and energy storage. I'll assume we are going to have a pump that runs on 20 watts and is on 24 hours a day. That is going to use 480 watt hours per day. If you only run half the day, then 240 watt hours.

A 12 volt, AGM, deep cycle, 90 amp hour battery will store 1080 total watt hours of energy and if you never discharge it below 50% capacity it will last about 7 years if charged properly. This is the most expensive part of the system at $169 with free shipping on Prime.

To charge this battery you need a 100 watt, 12 volt solar panel at $79 and a 20 amp waterproof charge controller for $20.99
( if you find a deal and get two panels or a larger one, I sized the controller to handle up to 240 watts total. Extra watts on the panels will help on cloudy days but just be sure they are nominal 12 volt rated. note: 12 volt panels produce ~18 volts)

Then, the final part of the picture, since that air pump I suggested is AC powered you'll need a 200 watt 12 volt DC to 110 volt AC inverter. I know it would be more efficient to keep everything DC, but the AC choices for pumps is huge and DC is tiny and much more expensive.

PS. I did find some DC pumps by searching for minnow tank aerators but I doubt it would be rated for continuous duty like an aquarium or pond pump would be. Would still be interesting to test. It would easily run on the battery above for more than 4 days for a 5.6 Liter per minute / 88 gallon per hour 12 volt DC pump drawing .46 amps, =~5.5 watts. This might work for a 100 gallon pond, or for sure two of them would handle a 150 gallon pond.