Join Date: May 2011
Location: Elk Grove, California
Yup, that sounds about right for ADA soil from what I've read in their book. Probably designed it that way so you have to spend more money. >_<
If you have a choice, I'd go with a c02 injector for lowering pH and RO water for lowering KH. You have to add a remineralizer like Kent's R/O Right though. If you add ferts regularly and you aren't using some of the extremely difficult plants, then in my opinion, the benefits of an expensive plant substrate aren't worth the trouble and money. If using a c02 injector, it's also best to set up an airpump on a timer to come on and aerate the water, otherwise you'll experience a pH CRASH.