Backyard Aquaponics
A place to discuss aquaponics

That should work pretty well

I would have the pump pumping up to the bottom of the beds through the current drain pipe, and having the beds overflow out the top pipes and back to tank. When the pump is turned off, the water will drain back out of the beds via the pump (backwards). Will require a few more bulkhead fittings, but would work very well. Will give you maximum flow to fill the beds, and maximum to drain. A "solids" handling pump is not super important, because the fish crap is not really solid. None of my small pumps have complained.

Tallebudgera Valley, slightly cooler than right on the ocean, down 2-3C at worst during winter, usually 5Cnight and 22C day. Summertime I guess 20C night and 32C day on average.

Beautiful one day, perfect the next they say.

Given that my tank isn't buried, I presume I need to insulate it and provide shade?

Cheers,
Arran

Jees I hope so, that is the premise I have been working on

Best to start small... most of us did - its a good way to learn!

you might struggle with them over winter, but summer sounds like a go-er

From one bath tub to ... still growing

Correction, mean min summer temp is 20C and mean max is 28C. 30+ days do happen though.

Likewise in winter, " minimum is 9c but it was 5C last night. People run AP systems under far worse conditions than these. One of my main concerns is too much rain....we've been getting LOTS of rain for the last couple of years. had 2 x "1 in 100 floods in two years. Both the tank and the beds are only partially sheltered from rain so some dilution will no doubt occur.

Have you tried that before? I would expect the the low head from the beds draining to the tank would not be enough to overcome the backpressure from the pump...there would have to be some back pressure wouldn't there? I think I'd need to test that theory before plumbing it in.

Why would that require more bulkhead fittings? Would I not just plumb the pump up t the current outlet?

And lastly, wouldn't solid pumped up, just get flushed back into the FT?

Some solids might flush back through the pump but not too big a worry. Definitely doing a simple flood and drain system where the beds are higher than the tank, using only one pump and no sump makes for a simple learning system so long as you keep your stocking rates kinda low as you learn.

The larger the pipe and pump, the less clogging issues you will have. (small irrigation pipe and the even smaller fittings for it tend to require regular cleanings.)

Venturi drains are really not difficult but only useful for a CHIFT PIST system. If you didn't want to deal with raising up or supporting the grow bed bins, then a CHIFT PIST system would be great though you would then need to dig a hole for a sump tank so the basic system may be better for a first system.

I would actually prefer to raise the bed well off the ground, because we're in the sticks a little bit we have lots of bugs and I'm hoping that raising the beds will reduce bug problems. If nothing else it will stop the Indian Runner ducks from denuding the lettuce and the dogs from pinching the strawberries

My dog eats our sweet peas and climbing beans. And any garden not fenced off he thinks is his play ground.

Yes done it before, the pump runs on a timer. 15 mins on 45 mins off. While pump is running beds fill, when pump stops the water flows back through the pump into the tank.

No problems with "solids".

Extra bulkheads because you would be going through the bottom of the bed, and through the top.

Dont give up on the vertical rack of PVC idea, its a great way of using the vertical space. It does work, you just have to make sure that you filter out all of the solids before the water runs down the NFT pipes. If you were going to put a gravel filter before the NFT I would recommend that you either dont plant anything in it, or you dont plant anything that you are going to harvest and leave roots behind. As the roots break down the organic material eventually finds its way out again which is what I'm having problems with at the moment.

KE, is that top pipe just filled with gravel?

Ok, I've got 4 x 160L black plastic tubs from bunnings, a 1000L tank for the fish and will start plumbing this weekend. I'm in contact with SEQ Fish and he reccomends Silvers for aquaponics which will be available in October so I'll get things up and running with goldfish as seems to be the norm and put the silvers in later.

My question is, how many should I order? I know my system will only handle about 25 adult silvers but I should surely account for some attrition and get more than that. Is there any reason NOT to get say, 50 of them and see how many survive? As the fish grow, the tests will reveal whether there is too much of a load on the system and I can feed some to the dogs/cats/chicken.

They are usually only around $1 each for fingerlings, so get 50, and by the time they are full grown, your system will have expanded