Backyard Aquaponics
A place to discuss aquaponics

So i've decided to go with custom grow beds & fish tank. This will be my first aquaphonic garden. I've sourced some IBC's and the cost to build these will be only about 1/2 the cost of the IBC. I decided to go this route for aesthetics rather than cost. I'm waiting on some money to come in so i've got a few weeks before construction will begin.

The white is a pond liner. It is rolled out then smashed between the frame and a 1x1. The bottom of the bed is supported with 2x4's 16"oc

I'd love some input on this. I've calculated that the water in a 12"x24"x69" area will weigh 997lb. I'll likely add some support in the middle of the bed as well.

Any criticism will be greatly appreciated.

Looks pretty reasonable, I think your heaviest thing will be your media rather than the water, if you're using a rock media in the system.

Looks good. Have you estimated a price to build?

$46 for the lumber & $40 for the pond liner. I'm looking to make this a bit smaller to get 2 out of 1 pond liner. I think i can get this down with some cheaper 4x4's if i can find them.

This is about the same volume as a 12" top of an IBC. Obviously if your paying less than $86 for an IBC your also getting a water tank & Stand.

So after seeing those number's i redesigned the frame. The pond liner is 9'x17'. So i changed the dimensions from 8'x24"x12" to 6.5'x30"x11" (The other should have been 11 too for the overlap on top to be screwed down.

The legs are 2x4 rather than 4x4. I'm having a hard time understanding load weight on structures. So i'm really unsure if this thing will hold... Anyway without further ado.



This one costs $18 in lumber & only uses 1/2 the pool liner. So $20 for the liner. A total of $38. Since i was planning to have two anyway, that'll be $76 for two.

Just saw the media question. I'm going with expanded clay. I've found some locally just waiting on price. It's looking like a truck load for $100~ It weighs 65lb SQft wet.

dont forget to add the weight of your water.... at 62.42 lbs (23.3 Kg) per cubic foot

jT

Thanks for the tip! That's what i designed it for before thinking about media. Luckily media is only 3 lbs cf more.

Does anyone know how to calculate how much weight a structure can handle?

I would add diagonal braces to all the legs. Otherwise looks ok from sketch, make sure the weight/downward pressure is located on TOP of the legs

I would beef up the legs a little - at least use 3"x3" and diagonal buttressing and/or horizontal framework.

With the kind of weight you're talking you don't want it to get wobbly, and those legs look no way sufficient. Remember the GB is going to be a workplace, so you really can't overbuild it. Make it earthquake proof, which means as cubic as possible. You don't want to be in mortal terror when you have to spend half and hour underneath it fitting the siphon plumbing.

Well put advice!

Where are you going to get the expanded clay for that price? All I could find was $36 a 50 liter bag and no discount for volume. And shipping on top of that.

Spend a little extra on the frame. It might fall on you and that would not be good. Triangle bracing is necessary with this weight we play with.

I know this been several years ago but this is exactly what I would like to build but 3 beds instead of just one. Did it come out ok? Could you post pics of it now? What did you change and what would you change if you was to build it again ?

Even today, 2016, the best price I have so far, is $25 USD / 50 liters, here in Cambodia.