I use z7 water treatment and don't use any kind of cleaner's anymore.
I used just about everything at one time or another before I found it.
The z7 takes care of all of that and makes DWC much easier.
There is no need to flush until the end when using it.
I've seen this recommendation quite a bit lately. Can you give an old man an idea of the cost on the z7 ? Tnx.