Inaugural Post -- Fantastic water quality results today.

API makes a great all-in-one water test kit for aquariums and water gardens

I decided to test the basin water today. For those unfamiliar with our green wall design, we use a reservoir at the base of the wall to hold water, which we pump to the top for trickle-down irrigating. Because the water gets reused several times per week, we have to keep an eye on our ammonia, nitrite, and nitrate levels. Austin tap water usually has high pH as well, thanks to all the limestone aquifers in central Texas, so we test weekly to keep our reservoir water under 6.5. 

The last time I tested the reservoir, our numbers were terrible: ammonia was through the roof, pH was high, and nitrates were at a dangerous level. I was definitely surprised by the results this week. 

pH -> 6.4

Ammonia -> 0 ppm

Nitrite -> 0 ppm

Nitrate -> 40 ppm

I installed an aquarium filter about 2 months ago, which I was hoping would help reduce the concentration of ammonia in the water. It looks like the biological filter finally established itself since our ammonia and nitrites readings are coming back so low. I expected to detect some nitrates since we do use liquid fertilizers that are added to the reservoir, but 40 ppm isn't cause for concern. I can reduce that concentration by doing partial water changes on the weekends. The reservoir could really use one this weekend, since the water is becoming a little murky from dropped soil and algal growth. Establishing the nitrogen cycle in an aquarium or water garden is a big step towards stable, healthy water quality, so I'm really glad we've reached that stage of maturity in the reservoir. 

 

On a separate note, I'm still seeing yellowing leaves widespread throughout the wall. My first instinct is that I'm over-watering. But since I've been meticulously checking soil moisture recently, I don't think that's the case. It may just be transplant-induced stress. I'm going to keep my eye on it.