I have noticed that the Zone has changed.. it no longer has the blue tint and flakes in it.
Can anyone tell me how long it stay active in my rez? does it need added back like bleach after a few days?
I've used DM zone during my 1st encounter with slime. It is a great sterilizer and if you continue to use it then you would add more as you top off water.
NOTE: zone does not react well with organic nutrients, my experience with it I had best results when running zone and base nutes only.
You should look into brewing your own ewc tea. Google heisenburg recipe. This should be used from beginning of grow until the end.
I use it in my RDWC systems since I have lots of pipes and sprayers that the benny teas and aquashield muck up after a few weeks..keeps everything much cleaner. I havent noticed any change from the stuff when I first started using it back in 2009 to the stuff I just bought last week..always had a puke green tint with no flakes for me..