Backyard Aquaponics
A place to discuss aquaponics

The airlift is external to the fish tank,it runs the system,the water is gravity into the dwc,there are pics on my thread,i honestly don’t feel you need them in the dwc providing you have air stones in the bed.
Your bed construction,again this is just me,but i would be happier with a cap piece and then verticals fixed at the bottom and top to ensure there is no movement,especially at the joints between your boards,you are using some hefty old boards but they will still move under the weight of the water.
The 90 joiners on the inside as well, if you have liner offcuts put a piece over the clip before the liner,just as an extra insurance.
The wood looks pressure treated,how about the ply ? if its not give a quick coat of something just to protect it,if by any chance what so ever you get a seep of water between the liner and wood it just sits there,it takes for ever to dry,not good for ply.
Air pockets in the float,to be honest i can see a difference in growth but its months in between crops it hard to remember,this lot is going gangbusters,BUT,the temp has come down,its now a system on its own with lower nitrate level,i have sourced one inch net cups designed for foam cubes and i am dosing differently.One thing i have noticed is i have two distinct type of roots,the roots in the air gap are pure white and furry,when the root touches the water the hairs disappear,not sure what this means yet.

What dasboot said about raft build.. You need supports on the sides of your raft to prevent them from bowing or worse..
Interesting build.

Wrong thread..lol

Dasboot,

Thanks for the positive criticism. The ply it pressure treated also so no worries there. Was also thinking of covering over all the galvanized bits before dropping the pond liner in. I was just thinking of replacing the air stones with the airlifts due to the lack of maintenance needed with them. They should keep the DO as high as the air stones in this configuration. But I could be wrong.

Swede,

Thanks for your comments. I will add more bracing before I fill it. Just to be sure.

Sounds safer. Keep the updates coming.

Will do

Drop the air lifts go with the air stones,put one every 4ft.....

I feel like we are both doing almost the exact same thing. I'm just about to add photos of the o2 setup I just added to my DWC. Meanwhile I'm also dealing with some warping at the top/middle of the wooden framing I'm about to cut some steal bar with the angle grinder.

awesome price... I actually have 2-3 left over bags myself still, but I would have contacted them had I seen it earlier.

Pond,

That is not good news. As I believe my DWC is as least 3 times the width of yours. I will have to recheck your thread. If I remember yours is about 2ft across. Mine is almost 8ft across. I don't know the calculations but I don't think they are not linear. Anyway rough guestimate, I will be dealing with at least 3 times the water weight. So at least twice the lateral force Maybe Stu will show up and help out I am leaning towards putting a cross brace or 2 across the top. I will just make sure I don't plant anything short and squatty next to them.

Dont stress yet, mine is only 2' wide but its 15' long so I believe that is the cause. My length distance is very long without any top brace, and it only bows about 3/4" when full so its hardly moving I just know people are going to want to lean or sit on it and I don't want to be quietly watching in fear that its going to end up becoming a dunk tank because my building work is based on youtube and BYAP input instead of actual carpentry trade work like so many of you guys here.

Pond,

Mine is also 16ft long so double trouble

Has anybody had any success with this pump?
https://www.hydroponics.net/i/132951

I have 2 of them, been fine for the last 15 months. easy to rebuild, I had one flood when a check valve went bad. Dried it all out and put it back together and it's runs as good as ever. They're a bit noisy. If you can suspend them, they are a lot quieter. This is another brand...I think same pump series.http://www.amazon.com/Hydrofarm-AAPA110 ... QB5VVTGWZD