Kinda of wierd thing with Plantex, I used to mix a stock solution that was a brown color when mixed and noticed after about 2-3 weeks it would turn more reddish, the color deepening over time. Also algae issues and lowsy growth. I stopped mixing stock solution and started dosing directly. Growth exploded and algae went away in 2 weeks. No other changes to the regimen. Anyone seen this before? Possible the stuff actually rusted and iron became unusable??