Backyard Aquaponics
A place to discuss aquaponics

Hi all, I am an elementary school teacher in MN. I have had a classroom aquarium for some years (300 gallon) and just this week I added a 3 square foot flood and drain grow bed above the tank. Thanks to this forum and other sites for providing me with the info I needed to pull this off. So far the plants and fish are doing well and all levels seem good except the PH has me a bit concerned- 8.2.

Gotta figure out how to add images...

Welcome to the forum . Unless you have some calcium carbonate in the media you used the pH will probably come down as nitrification kicks in. You can also adjust it down with Hydrochloric acid (aka muriatic acid) if you're desperate to get going and avoid some nutrient lockout issues (but I'd just wait). Until the pH comes down you'll need to either spray apply an iron supplement or get EDDHA iron chelate which is available at higher pH and can be added to the system water.

I tested some of the rocks in the aquarium with vinegar. Some produced bubbling effect (Calcite?) and a couple looked like I had dropped in an alkaline seltzer tablet. Got rid of these rocks. The grow media is inert expanded clay and lava rock.

Welcome to the forum...

>> Gotta figure out how to add images...

Instructions here (top two threads) > viewforum.php?f=4

>> couple looked like I had dropped in an alkaline seltzer tablet. Got rid of these rocks.

that should help.