Backyard Aquaponics
A place to discuss aquaponics

I did something similar by adding a valve for back-pressure in the line at the end of the grow beds pipe which returns to the FT. I kind of wish I hadn't and just planned to run all the water through the filters. One benefit is if the filters get clogged and create back pressure, the FT water overflows into the ST. When all flows are set correctly the FT does not overflow in the ST. A few variables such as gunk on the pump screen or gunk in the pipes can throw off the pump parameters, especially flow.

Yes, you can kick back the flow to the FT. It would be ideal if you have it complete some sort of mech/bio loop before return back to FT and not rely solely on the filtration from the beds.

Pumps in AP/KOI/FT/etc are like oil threads in auto/bike forums......no systems are built ideal and some get great service life while other conditions cause failure. Throttling would be liken to head pressure. Specs will state a max head where the pump slow to a trickle or cannot overcome anything.

In one koi forum, testing is being done to see if the specs/flows/energy use are in line with what manufacturers claim. It will be interesting to see the results. I should also state that these will be done @ koi shows for those aware or attendees to witness. Hopes is to have the brave vendor step up and have it performed as designed or be a failure and get some accountability on their part?

Only thing I would do is get a larger pump as opposed to the bare minimum. Running wide open at the limit of max output can only be done for so long before things start to wear...... Cushion of 25-50% on small mag driven type pumps I have seen as a general guideline (no steadfast rule and can become very cost prohibitive in the commercial pumps if the line of thinking used....)

One other thing (have not done on paper, but seen in tinkering with system as running), each fitting that cause a change in direction comes with some sort of head pressure to overcome. So even if you operate within the overall height of the pumps ability, you may be exceeding in your pipework?

Adam

Well stated BroHay. I can add that the valve at the end of the pipe going to all the beds needs to be adjusted first. This evens out the pressure to all the GB valves. I wish I had made the outflow from the GB lines go to the filters instead of the FT. Because of that overflow (skimmer) from the FT occasionally has leaves and floating fish feed in it. Thank you Adam, for always helping me see clearer. I hadn't until you said this realized exactly what the issue is with the ST getting gunky.

I need a pump that I can plug directly in a 24vDC battery bank. It seems the Jebao DC 6000 and like use a power supply to convert AC to DC, however I wonder if we can leave the power pack off and go straight in the batteries? Perhaps via a 30w power regulator? I thought I read that this wasn't a workable plan because of the secondary power inverter and regulator in the controller?

They have some DC battery power pumps on EBay https://www.ebay.com/itm/24V-Brushless-DC-Water-Pressure-Pump-DC50E-24150A-87W-15m-Power-Flow-Adjustable/152916495866?hash=item239a888dfa:g:MpgAAOSwB09YFG6H
I found more information http://www.dcbrushlesspump.com/Brushless-Dc-Pump-(DC50E)-p36.html
Max flow rate
17L/Min(4.5GPM) ---2 phase 20L/Min(5.5GPM) ---3 phase

There's a power pack to convert 230V/110VAC to 24VDC, that feeds an inverter which inverts the 24VDC to low voltage 3phase AC. I can't see any reason not to supply the inverter with DC from a battery provided it is regulated to 24VDC, and doesn't vary with battery voltage during charging, which may be up to 30VDC during the absorb stage in cold weather for flooded Lead-acid.

Thank you Gunagulla.
That is what I needed to know.
I'll figure out a DC regulator for it.

I noticed some people were looking at DC pumps for solar and suggesting 24v pumps to protect against over voltage. Although new to aquaponics/hydroponics I know just enough of electronics to be dangerous. So here is my take.

The problem with using a pump/motor to handle a variable voltage is for example if your pump runs at 24V then your pump's best flow/efficiency is at that voltage. Drop that voltage off (some models may differ) to a 24 volt pump and the strength of your pump is going to drop off a lot which is not good if your looking for a consistent/constant flow.

For me I wanted to use solar only that ran only during the day time (as I recall roots only really draw any significant water while the sun is shining) and without using any batteries that wear out. So I chose to go with a fixed voltage high efficiency 12V pump. My amorphous solar panels (works well in lower light) puts out 22V in peak sunlight and slightly lower voltage on cloudy days. Rather than sending the 22V to the 12V pump direct and hoping for consistency, I instead connected the solar to a 12 volt "boost/buck" power converter. My pond pump has a digital flow controller built in that is sensitive to low voltage which is why I went with a boost/buck converter. Otherwise if it was just a 12V motor I would of went with just a plain "buck" converter as they are little more efficient.

The way a boost/buck converter works is it takes any voltage you throw at it and converts it to a steady "12 volts DC" (or convert to any other voltage you may need if you adjust it properly). "Buck" will lower a higher solar voltage to a flat 12 volts and "boost" will raise a solar voltage below 12V back up to a stable 12V (as long as the current is there to support the conversion). A good buck and/or boost converter is VERY efficient. They do not waste power (unlike a motor running below voltage specs) as they convert voltage AND amps. For example: Say I had solar panels putting out 24 volts and needed to feed a 12 volt pump that drew 1 amp. A good buck converter would draw 24 volts and .5 amps (plus a tiny amount of power to run the buck converter) from the solar panel and convert that to 12 volts and 1 Amp for the pumps power draw. Plus when the voltage of the solar panels changes due to lighting the converter will adjust the voltage to a always stable 12 volts DC. Boost works the same way in reverse raising the voltage. This voltage to amps efficiency allows you to use smaller groups of solar panels to power pumps remotely. Right now my solar panels are powering my pump from 6AM to around 8PM sundown (this time of year) without batteries.


So here is what I used. I made my "test" aquaponics only 1 tube this year because if I screwed up and things died I would not have a big loss as I learn from my mistakes. Next year I'll expand a lot more.

For a pump I am using a 12V DecDeal pump at just $10. It's brushless (magnetic spindle) and draws average (I tested at my bench power supply) .8 amps at 12 volts (10 watts). It's easy to clean and it's POWERFUL (400L/H flow) for the power used. I am running off the pump a 40 foot water feed line (spliced in the middle is a capped plugged 3 way water splitter=high resistance). The pump raises the water through resistance at least 6 feet up to my PVC grow tube over that 40ft run and it's still a good flow.

The pump has good reviews for longevity (my mileage may vary as I just started). However it's so power efficient my plan is to buy 3 more pumps. I will use 2 pumps feeding (through separate lines) my grow PVC. So if one pump fails or needs cleaned the other pump will still be going and I will have 2 more for easy replacements.

Bought my pump here: https://www.ebay.com/itm/Mini-DC-12V-4M-10W-400L-H-Flow-Rate-Brushless-Motor-Submersible-Water-Pump-Home/273122860539?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Pics:

Screwed pump onto stake which I hammered into the pond bed. I set it so it would be "mid" level in the pond and not suck up all the gunk settled on the bottom of the pond.



and






Here is where I got my boost/buck converter: https://www.ebay.com/itm/Automatic-Voltage-Stabilizer-Power-DC-DC-Boost-Buck-Converter-Regulator-Low-Heat/222703767940?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649


However if you have just a motor I found a really good and very efficient buck converter here: https://www.amazon.com/gp/product/B00VWLT2KU/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1 You'll need to put it in a water proof enclosure. But it runs cool and uses almost no power.

Like everyone else I'm learning as I go. But I hope this information is helpful to some of you out there as we all share.