Backyard Aquaponics
A place to discuss aquaponics

A 1/2 hp pump will be way overkill

It's the smallist one I have. I do have a davey pressure pump but it can lift water onto the roof.

Hows the best way to cycle the pool. And how many fish can I put in it? I'd like an eating fish that can handle the lower temps.

For starters whats you water temp?

Decent sized silver perch will tolerate temps to 5 deg c or so. Fingerlings will start to die at 15 deg c.

Trout like cold water, but cant tolerate over 24 deg c or so.

6 x 1/2 barrels will support 25 to 50 1/2kg fish once cycled.

What is it now, middle of winter. Water at the bottom is 10 deg. Also have a lot of room for more barrels.

For cycling, use humonia or urea. Small amounts and test.

+1 on the using small amounts or urea or humonia for fishless cycling. (500 ml doses might be all you need for humonia) Should probably wait till all the chlorine has been gone for a bit though.

If you want to make the barrel set up easier to shift or change, perhaps sand bags for support instead of concrete. Or just cut the barrels in half the other way and they will be self supporting.

A 1/2 HP pump may be overkill for the amount of grow bed you are planning right away but you can always divert most of the flow back to the fish tank for circulation/aeration. My first pump was actually 1 1/2 HP from an old above ground pool. Biggest problem with a way overkill pump is the power use. If it's an energy efficient pump, the fine but if it uses lots of power, you may be better off doing some shopping. My old pool pump used around 1200 watts or more while my new efficient pump is around 220 watts with only slightly less flow than the bigger pump.

If you do auto siphons, you need to be far more careful about the flow rates into the beds compared to the siphon outflow rate since there is balance needed there. If you are going to use a timer (make sure the timer can handle the amperage of the pump)

Currently the pool runs a 3hp on a timmer so the jump to a smaller pump shouldn't be too bad to start with. Got a solar pump comming, going to use that to put a little air and movement in the water.

All the drums have been cut in 1/2(not the long way). I'd like to have four times this amount but have to crawl first.

Had a go at auto siphons with 19mm tube on half barrels. It worked, no gravel in them . Was a pain bending that tube so it didn't kink
Do I need them when the pump will still be able to fill them while they drain. But later when I add more barrels they will need them. Bugger. Might have a look for some better fittings and tube, PVC bends really well when new.

More of a chlorine smell out of the tap than the pool water now. Got to get a master test kit. Don't like the test strips ones much.

+11 for cutting them in 1/2 through the waist.

19mm tube can handle 1 x 4500 lph pump pretty well (18 beds)

Well this is the drum with an auto siphon on the side. As you can see I got out of the bending. Only just noticed the PVC tube on another thread. Have to make some of them up before I add the gravel. I'm going to be adding a layer of large gravel to the bottoms, same stuff you would find near railway lines. or broken brick. Then fill the rest up with smaller size gravel. Both of these 19mm tubes go into a 90mm PVC back to the pool. I can have 6 barrels connected to the same PVC line and later add the same setup beside it.

Another way to make the loops is to use grey water hose (the corrugated plastic stuff)

This works for me - the larger stuff is cheaper here, so its 2 thirds large media and 1 third finer stuff... but dont go toooo large as the finer stuff just fall down between it...

I was thinking clear tube to make finding any blockages easier,, then have the clear tube covered with split-flexi conduit,,, same as the grey stuff OBO was talking about, but split so you can easily add/remove it.

Does using clear allow algae to grow in your siphon. I know with regular water the stuff grows in clear. AP water would be like miracle grow even with the conduit blocking out most of the light.

I was toying with the idea of joining the barrels together so if one siphon fails the drum will still be drained by the others. Just depends on how uniform they fill so I can see inside the PVC if one is draining slowly.

Also liked the idea of a sealed tube that would float inside the PVC so I could see the drums are filling from a distance. Also by pushing them down they could break off any roots before they get to the siphon.

yep clear will clog up quick smart