Nitrates in tap water, should I use RO?

Discussion in 'Aquarium Water' started by bajan brit 76, Dec 4, 2012.

  1. bajan brit 76

    bajan brit 76New MemberMember

    hello ,high nitrates is killing my fresh water tank -and its comming from the tap,if i use R/O or D/I with the water changes will it help? tested the tank water is it 50ppm
    Last edited: Dec 4, 2012
  2. chevyguy8893

    chevyguy8893Well Known MemberMember

    Mixing RO water with tap should cut down the nitrate levels, but it would also change the pH, KH, and GH. So, that would mean that you would have to change smaller amounts of water so you don't shock the fish with the difference. The other thing is with the KH being dropped from the mix the pH buffering capacity is reduced, and may drop too low causing swings in the pH.

    You could try mixing a 50/50 mix of RO and tap water to see where that puts you for nitrates, pH, KH, and GH. Then adjust if needed till you get levels that are safe. I believe a KH of 3 dH is the lowest to keep from encountering pH swings.

    I would think the RO/DI water would give you a little more control, since that water is completely stripped of minerals and the tap water would be the only source of impurities. Whereas water only running through a reverse osmosis process would still contain some minerals. Either way the nitrates should be cut down, but how much depends on the mix.
  3. OP
    bajan brit 76

    bajan brit 76New MemberMember

    thank mate, sorry for the late reply.