I've done a lot of experiments with DWC, aero, and coco with enyzmes + beneficial bacteria. What I've found is the prozyme seems to work the best, followed by hygrozyme. If your plants roots are healthy and white, theres really no need for the enzymes. However, I've run into root rot scenarious in all different kinds of setups (aero, dwc, coco, ebb and flow, hydroton, etc.) and when NOTHING seems to get rid of it (sometimes underwatering will help stop root rot) I resort to dosing the res with h202 + enyzmes. Obviously if you are using beneficial bacteria this will destroy the colony, however if the roots are rotting then obviously they aren't doing their job too well anyways. I've seen what h202 and the enzyme mix can do, I've brought back root systems completely rotted and dead (and infested with root knat larvae). Like I said before, if your plants are healthy, you don't really need to use the stuff (especially since its $). However in light doses I believe it probably makes for good preventative maintenance (keeps things healthy, and dissolves dead roots, preventing possible root rot infections). IMHO this stuff works so well that everyone should keep a gallon on their shelf, just in case your plants just start dying for no reason...it has saved me countless of very important plants that would have not made it otherwise. I should also mention that just dosing with h202 works well also, but the dead root tissue remains, and once the dosing stops, the plant begins to die immediately (from infection of the dead root mass). Constant dosing with just h202 can also rejeuvanate a plant (I've done this before as well) but it takes much longer. Keep those roots blinging white!