Backyard Aquaponics
A place to discuss aquaponics

Thanks Macnet1



Peter,

My Duckweed is not doing all that well at the moment and it has died off by about 90% due to the cold weather getting down so low at night. It also now has algae growing underneath it and that seems to protect the remaining 10%, last year when the same thing happened I just changed the water and got rid of algae and the duckweed started growing again.

Duckweed can tolerate temperatures ranging from 6 to 33°C, the optimal growth range is 20 to 28°C, but in the 1/2 barrel it's in the water temperature gets down to 1 & 2°C overnight and it dies off, I might put some of it in a bucket and sit it near the window in the garage and see what happens.

I'm currently turning the pump in the AP system off at night and the fish tank temperature hasn't gone below 8.9°C on the coldest nights but that's because of the water volume, the 1/2 barrel temperature drops far lower than that.

Duckweed needs still water, I had an air stone in there for 6 months up at one end so it didn't disturb the water too much and it worked well but as soon as it got cold it made no difference at all

I don't worry too much about it because I have a mate with it growing in a pond and he just gives me a container full whenever I ask for it, I've never seen his actual pond, his wife and mine play Bingo together and the Duckweed just arrives from Bingo so he might have his pond at the back of the Bingo hall

A couple questions: Your MMBF and RFF are 75 liters each? How large is the system which they are filtering? I'm working with nearly ten thousand liters. Is my 200 liter barrel for the RFF good? Cheers and thanks for the PM

Hi Brian,

The barrels are around 75 litres each if I remember correctly and the 2 MBBF's have 25 litres of K1 Bio Media in each barrel. I'm running approximately 2,000 litres of water, your 200 litre barrel will perfect.

Just had a read impressive setup
How do you find the wicking beds

Thanks Milne, I've been a huge fan of your wicking beds and wished I'd read up on yours before I went ahead and built mine, I could have improve on mine by following your advice.

My wicking beds and pots do alright but there's room for improvement, there's always the next one

thanks Joeblow, let me get a clarification on something please: Your dual SLOs feed RFFs, them MBBFs or MBBFs only? Is there a definitive set of instructions for RFF here?

Brian I have one SLO feeding a RFF then a MBBF, the other only has a MBBF there wasn't room to fit another RFF but because the RFF works so well I now have plans to fit one to the other SLO.

It will need a lot of plumbing and I'll need to run the pipe behind the fish tank too be able to fit it in.


My vertical inlet pipe it finishes about 60mm lower the outlet pipe, both pipes are 50mm diameter and the lager pipe is 150mm diameter. There are 2 -45 degree angles in there instead of a 90 degree elbow to help the water flow and the outlet ball valve has a fitting inside the barrel that touches the bottom to remove all the solids from down low.

In bottom photo the RFF is on the left in the and the MBBF on the right, so the water leaves the RFF at the top and enters the MBBF at the bottom.

Brian I have one of those brown barrels you will be using for your RFF and tomorrow I'll draw up where I think your pipes should enter and leave the barrel and either post it here or PM you with all the details.

I've been working on setting up a vinyl cutter and software for a equipment rental company for just over 11 hours today and I'm too tired to do any more tonight.

Thanks and good night

I run 2 - Resun ACO-003 65 lpm Electromagnetic air pumps and a 12 volt Hailea ACO-003 60 lmp Air compressor as backup air. The 2 Resun pumps run 24/7 and the reason for running both pumps is in case one should stop running for any reason or breakdown the other pump is still delivering oxygen to the fish.

Each of the 3 pumps had a manifold with 6 air lines running from each manifold, a total of 18 air lines and the 12volt Hailea also had 6 air stones sitting on the bottom of the fish tank doing absolutely nothing unless the power dropped out.

The 2 Resun pumps were starting to get a bit noisy due to both old age and back pressure from long runs of 6mm air lines so I decided to run a single 25mm PVC pressure pipe the full length of the system and use shorter lengths of 6mm air line at the points around the system where I needed air.

I drilled & tapped threads into the PVC pipe to take Stainless Steel 1/8" BSP x 8mm Barb Hose Tail connectors and to gain a thicker pipe wall for the threads I used 25mm PVC joiners doubling the wall thickness where I needed to place the hose tail connectors.

It all worked a treat and the pump noise was definitely a lot less than it had been and there was plenty of air after a bit of fine tuning, obviously the air lines closer to the centre of the long run would get more air than air lines closer to each end.

The 6 air lines and 6 air stones from the 12 volt Hailea air compressor were now not needed, or the 3 - 6 outlet manifolds everything was now running through 25mm PVC pressure pipe, I had lost 18 long lengths of air line and it was all working far better. With everything running together I almost halved the number of air stones needed. In the electrical box the air lines dropped from 18 to 3 making things a bit tidier in there.

I stood back and admired my work and then it hit me: with a long run of 25mm PVC pipe and all the glued PVC fittings with adhesive exposed to the sun all day and temperatures in excess of 40 degrees Celsius in summer. I asked the plumber about the PVC and adhesive giving off fumes in the warmer weather and he said "it shouldn't" he didn't sound to confident and the air in that length of PVC pressure pipe would get very hot and only add to the problem of keeping water temperature down in summer.

So I decided to lose the long run of PCV pipe and change it for a 25mm metal water pipe manifold and that would still lose most of the air lines and not have a lot of tubing exposed to the sun and totally without any adhesive or PVC fume problems.

This is the replacement, the metal might retain a bit heat in summer but it can be shaded pretty easily.

It's quite a bit more efficient than the long run of PVC because the outlets are closer together and are far more even in the output over all 5 barbed hose tails.

The12 volt Hailea ACO-003 60 lmp Air compressor is a lot stronger and seems to pump more air the both the 2 - Resun ACO-003 65 lpm running together (different style of pump)

I've just noticed a few bugs on my lettuce so it's time to try the Wood Vinegar Dasboot recommended, I've had it for a while and had no need to use it until now.

Nearly a week,how did the Wood Vinegar trial go ?

Hi Andy,

Mate I actually forgot all about, I've been very busy doing other stuff and hadn't been up the back for a few days. I noticed it today when I put some seedlings in and then it got too cold to do too much so I'll tackle it all tomorrow.

Plus I had a late night or early morning as they say watching a documentary I was involved in 10 years ago that has just surfaced until 2:00am this morning, it was released on Amazon in the last week or so I thought I'd have a look at it and then I didn't get up until late, that my excuse anyway

Andy I'll let you know how it goes and how quick I get a result.

Which documentary? Inquiry minds want to know