We were discussing something similar to this on this thead
. Although that thread seems to be about adjusting pH, later it's revealed that it's really about dying shrimp... the topic then evolves into a discussion about R/O.
Cycling vs R/O
Off the top of my head, I don't think that the cycling aspect of your tank is going to be impacted by using R/O water or not; Unless of course, something in the water is preventing the bacteria colonies from taking hold. (Perhaps the same thing that is allegedly killing the shrimp? Dunno.) However, using aquarium water prepared from R/O water can remove a few of the variables and make it easier to track down the problems you're having. Depending on how you reply to this, we could get into a discussion about the cycling aspect of your situation if you want.
Like you mentioned, you are going to have to re-mineralize the R/O water since the R/O filter is going to strip most everything out. You can use products like Seachem Equillibrium
(for GH) and Seachem Alkalinity
(for KH). Likewise, the corresponding Kent products are: Kent R/O Right
(for GH) and Kent Buffer
Alternatively, you can buy bulk and add your own mix using the following dry chemicals (my personal approach). The following chemicals will restore GH (general hardness) and KH (carbonate hardness) both of which are necessary for basic fish and plant health:
- CaCl2 (calcium chloride) or CaSO4 (calcium sulfate)
- Mg2SO4 * 7H2O (magnesium sulfate)
- NaHCO3 (baking soda) or CaCO3 (calcium carbonate)
- K2SO4 (potassium sulfate)
I purposely didn't include chemicals that would be specific to plant nutrients since you may have your own fertilizers that you use. The chemicals I listed are for basic re-mineralization and are much, much cheaper per dose if you buy in bulk. (And the added benefit is you know EXACTLY what's in your water.)
You can buy the bulk chemicals from hydroponics outlets, home brewing stores, and RexGrigg
. These are just off the top of my head.