I use powder. But none is needed in reality. Plants want to live if you let them. I honestly suggest you check my journal and read up on my method. One of many and only middle of the road. Will save you some typing and not so educational discussions.
Here is the link. Fully pictorial as well.
I've been asked to share my simple and cheap methods by a few people here and abroad. I'm just sharing my opinion on the hobby. You are more than welcome to share yours. No haters please. I can't type. Am not a photographer. And just want to help others while being helped. So here we go. Current...
www.rollitup.org