5.6-6.0 is what I aim for. I have been feeding the smallest one every other day because I didn't want to make it any worse. I'll start hitting it everyday and see if it gets better. Are you familiar with house and garden cocos nutes? Are their dosages adequate or should I add more? I only ask because both of my plants are kind of lackluster in both growth and color. Also I've had healthy seedlings that sat in jiffy starters for 2 weeks after breaking ground and never showed a hint of deficiency even with non ph'd tapwater
I'm not familiar with that nutrient line. I run Jack's 321. I'm guessing if you searched here, you'll find a thread or two that address it specifically, which may help you answer your questions. And instead of adding additional CalMag, you can simply add a little Epsom salt which will up your current Mg without upsetting your current Ca level. No reason to add what the plant doesn't seem to be calling for at the moment. Good luck.
