Thanks Willie. I do feel a lil dumb. Lol
Thanks Willie. I do feel a lil dumb. Lol
Thanks everyone for the help. I just want to start out with good water. I'm worried about chlorine and city treated tap water and the copper water pipes in the house. I just moved to "the city" from the country with great well water. Lol
Its true that the membranes will last longer with softened water, but since most people that use RO are using RO mixed with tap, or tap only in some tanks, its a good idea to bypass the softener. The best thing, if you wanted to do a little extra plumbing, would be to have unsoftened water going into the fishroom for general use, and softened water going only to the RO filter.
On the other hand, I don't think anybody knows for sure how much sodium is too much, or what minimum level of calcium is required in water for growing healthy fish. Since fish get minerals primarily from food, the amount needed in the water appears to be very low, although I have read accounts of deformed fry in low calcium water. I bypassed my softener simply because I would rather have calcium than sodium. Calcium is at least known to be a beneficial mineral, while sodium is at very low concentrations in South American rivers. The harder the incoming water, the higher the sodium level in the softened water.
There's a lot of ion exchange at the gills so I believe water that's much lower in Ca, Mg and other naturally occurring ions can be detrimental to fish. I would definitely prefer Ca over Na or K so I would bypass the softener unless using an RO filter and remineralizing properly.
R/O filters were designed for desalination. They are much more efficient at separating water from sodium than dications like calcium and magnesium. By using softened water feed for your R/O unit you will get a lower TDS in your output, a longer lived membrane and less waste water. If you reconstitute with non-softened water (often your cold kitchen sink faucet and/or outdoor hoses) you will have a lot more than Ca or Mg in your water for water change than any Na that gets through a RO membrane.