Aquaponics - NFT test system rebuild

I mentioned I did a rebuild of my NFT test before leaving my system unattended, and as far as my attention goes, in the fore for four days.

Yeah I just wanted to say "fore for four" in a sentence.

It wasn't as fulfilling as you might think.

But this is what I did....

This is what I used to have.

Or at least this is the exit tube I used to have.

The inlet tube was even smaller, at 4mm.

It was getting itself blocked on most days.

This is what I have now.

Now I add the entire flow of my pump through the NFT test. I guess it's not really NFT now because its no longer a film of water, but rather a tube half full of water.

I went with 12mm poly because I have a lot of it, and a lot of fittings lying around.

12mm polly is around the same diameter that exits my pump, so anything that can make it through my sad little pump should flow through the rest of the system without blockage.

I drilled a bigger hole

And found some bits that should do the job.

At the time, I was also getting ready to go away for a few days, so didn't really have time to be fussy.

It would have been better to use straight fittings, and curve my pipes rather than have these right angle fittings as they slow the flow a bit, and I'm struggling with getting enough flow as it is.

It turns out, you can often force a thread even when your project is all plastic.

There has been a few times where I found it expedient to employ what I like to call "Force tapping" a thread.

It involves screwing something into a place where there is not yet a thread for said something. Oddly enough, if you unscrew it, you will often see a shiny new thread.

It even works when both parts are plastic.

It also ruins the thread of the thing you are trying to screw in, so be careful how you employ this method.

My next hot tip is to stretch an O-ring from a snap connector garden hose thinggy with some pliers, and gently force it over the thread you want to make a seal with.

Plumbing tape probably would have been better.

Actually, what would have been better, is whatever you would get is you went to the hardware and asked someone for a part that would do exactly what I'm doing. I'm guessing there is one.

But this looks pretty good, and as I strive for second best practice, I consider this as having exceeded my expectations.

I swamped the side the test system was on because I wanted a shorter trip from the pump, and a shorter return trip back to the fish tank.

I also mounted the entire thing onto some milk bottles full of water. This is an attempt to shed some of the heat that the PVC tube picks up on a hot day, and store that heat into the milk bottle heat sinks.

It should work a bit, but I'm not sure I'll need it any more because of the high rate of flow I'll be putting through the tube.

The new depth looks like this.

This is a bit deceiving because the water flows differently when the plants are in place, and it makes the other end dip a little.

The depth is now more like 25mm, where it was 5mm before.

It's very easy to check by lifting a pot out and seeing the water mark.

The new outflow into the grow bed now looks like this.

Due to the length of the tube, it now enters the grow bed from the far corner. This means it no longer dumps into the core tester.

There were no worms in the core sample I took last, and I'm wondering if having the water dump somewhere else might change that.

Today when I pulled up a lettuce, there was a worm within the root system, so they are in there.


[edit from the future - This turned out to leak a bit ]