Backyard Aquaponics
A place to discuss aquaponics

I haven't been doing much with this system. I really should replant a few of those towers. I just hated to pull the chard when it was still doing well.

Finally got new catfish fingerlings

How long do you expect it will be till they get to size TC?

I expect them to be nice size for eating in a year.
(In my warm climate and feeding them well they will probably reach a small edible size in less than a year but I like to grow em big.)

Nice looking tower setup TC. I was wondering if you reckon solids removal is important for tower systems? I'm designing my next upgrade which the missus have included PVC pipe towers as a must. Cheers

For a PVC type pocket tower with a gravel or clay media, YES solids removal would be recommended. Probably easiest by running water through media beds first before going to the sump and then with the clean water sump you can pump to just about anything.

For my towers which happen to be ZipGrowTM towers they are filtration. They are filled with a media that is literally designed for the purpose of filtering fish water and the hanging tower they pull into is designed to hold plants in that media to use up the nutrients. So, the zipgrow towers don't require extreme pre-filtering but a settling tank or some small amount of filtration to help keep the feeds to the towers from plugging up does help. Simply by having my fish water flow through a not clean water sump and putting netting material right around my pump I've had pretty good luck with the towers though algae and snail shells can still stop up the hole on occasion.

So the Tower System is expanding in order to become a commercial system.

The tunnel is getting troughs to collect the water from the 20 additional towers I'm getting ready to add.

Here are some pictures of the new troughs. The ladies over at Green Acres supplied the Durascrim liner for me to check out (they use it for Friendlies style raft systems) and I'm testing out a new method for framing water troughs to avoid the lumber/liner dangers.
I'll let the pictures do most of the explaining.

The troughs have survived the week+ we were away and have been plumbed into the system with water in them.

The top edge of the liner is clipped to the Rail using the PVC clips like one might use to attach fabric or greenhouse film to a frame. The 1 3/8" chain link Fence top rail is the same outside diameter as 1" PVC pipe. I learned this when I used the fence rails to build my Ant proof worm bin stands and used uniseals on the fence rails.

Anyway here are a few plumbing pics showing how I plumbed through the liner to attach the two troughs together.

Clean and straight and you don't need to worry about the termites huh? Inspired!

What do you think of the duraskrim versus epdm liner? What is the price difference vs epdm?

Very similar prices based on my sources. However the EPDM I have to also pay for shipping and I didn't have to pay additional sipping on the Durascrim. (I purchased through the ladies at Green Acres.)

The durascrim comes in a 6' wide roll and is white which is a major plus for many uses. However it is not nearly so easy to fold nice corners. But it isn't stretchy like the EPDM so is better for doing a trough with a radius in the bottom corners so the liner will pull down rather than pushing the side rails out.

for an in ground lined pond where rocks will be involved, I would still use the Firestone pondguard.
For Raft tanks and similar projects. I think I like the durascrim and my new method with the rails and clips.

Great idea TCL. I bet this would work with shedule 40 PVC as well.

I'm not sure if schedule 40 1" pvc would really be strong enough to support much and the process of pounding the verticals into the ground would risk shattering the pvc but I suppose you could try it. I only put vertical supports every 8 feet with the metal rails.

I agree with you on the 1" PVC and would never go that route. I was actually thinking more of 1.25 to 2" You would have to dig holes, place the pipe and then backfill with dirt. You can also buy tarp clamps and structural fittings up to about 2" - http://flexpvc.com/cart/agora.cgi?product=PVC-Snap-Clamps and http://www.snapclamp.com/prices.htm You could build in a cold frame above the DWC area.

Here's a system called Redi-footing which might be of interest for something like your system (in a sidebar, down a page or so) http://www.chiefarchitect.com/finehome/shortcuts-shed.pdf - with this system you could just attach the liner directly to wood.

still a bit to expensive but gives you the idea.

Because of my climate and experiences with liner touching wood. I avoid even pressure treated lumber touching liner anymore. Termite territory here.

Anyway, I've been using the fence rails and brace clamps to build other structures and have a building supply that will deliver (the rails are also the kind used for making greenhouses.)

That is a kinda cool fitting for putting the lumber on top of the PVC post though.

Forgot about those voracious termites of your's. Hope they chip their teeth on that metal