Home / Uncategorized / Life in the Greenhouse: Week Three- ph for P.H.

Life in the Greenhouse: Week Three- ph for P.H.

I find it funny that my initials are the same as the water test that has to be done three times a week. In an aquaponics system, keeping ph levels as close to 7.0 or neutral are integral. Combine those two and you have a bit of a challenge. Especially when you need to make adjustments.

On this day Ashley handed the testing kit to me after showing me how it was done. Easy enough. 10 ml of water, a few drops of solution; tip a bunch of time and match the color to the chart. We found that the water in the main system was on the acidic side so we added dolomite to bring it down. Why didn’t we just use calcium? Come to find out that calcium binds other nutrients in the system and makes them less or not at all accessible to the plants. No starving our greens!

Next I was instructed on how to test for Nitrates in the water. Wait, so there are more water tests that need to be done? Yes- two more actually. Both the levels of Nitrite and Nitrate need to be tracked. Metropolitan Farms grows plants, fish, AND bacteria. Although the bacteria isn’t a cash crop, it is totally necessary for the system as a whole to work. One type of bacteria take ammonia produced by the fish and excrete Nitrite while the other take the Nitrite and excrete Nitrate. Its Nitrates that make our greens so lush and growing. All these elements have to be kept in balance, though, because one being too high or too low can stress or even kill our plants and/or fish. Both the Nitrites and Nitrates were right on par for this day, though.

Testing the water for these three levels is part of the rhythmic life on an aquaponics farm. Most of the time it isn’t too exciting and this is a good thing. Its pretty amazing what can happen if you just let nature do its magic!