Backyard Aquaponics
A place to discuss aquaponics

I think he added something after the concrete leached and hurt his fish.

Hot molten paraffin wax? Ought to soak into the wood some before it cools. If you had big enough of a vat to melt it in you could possibly dip the whole board(s). Possibly smear some on and run a torch over it to smooth it around? Probably seal concrete as well. Hmmm. I will have to try some of that myself to see how it goes as I have a concrete sealing job coming up soon .

Hey Dave. I just want to add that I've read that Black Locust is toxic to cattle and horses but other animals don't have trouble with it (and use the pods as fodder/forage). Of course, caution is warranted but there is a big push to use it instead of very toxic pressure treated wood.

Bees supposedly love it.

Thanks CJ for reviving my four year old thread LOL.

Fwiw I coated my wood in my current setup that is over the water with Rustoleum marine spar varnish, well see if I grow a tail from that. Has a pretty natural oil smell to it. These pieces are not submerged but will get some little splashing action.