Backyard Aquaponics
A place to discuss aquaponics

Hey forums,

I've just completed a huge water change in my system an the PH is reading about 7, about 7.3-7.4 and I'm looking for safe ways to slowly move that PH downwards. I'm using a typical flood and drain style bio filter with hydroton, there is also a few remnant pieces of gravel from a previous experiment (I couldn't clean it all out).

The fish are Koi, Goldfish and some Minnows, all appear to be doing well. All my nitrate, nitrite levels appear to be in healthy range. The plants are various strains of Tomato.

Your PH is fine, the nutrification process will slowly bring your PH down but your close to nuetral anyway.

Is there any reason you want it lower?

Nope, I just thought between 6.0-7.0 was best for heavy flowering plants. Thank you for clarifying I love it when I don't have to do anything. That's essentially my goal in life haha!

You are right that nutrient uptake at lower PH values is better (between 6.2 - 7) but the difference is minimal and almost immeasurable. Your plants will still take on nutrients on a broad spectrum of PH. This chart shows what I mean.

Brilliant. Thank you for sharing that. I have no clue what molybdenum is though. How do I get that into my plants?