Cichlid Fish Forum banner
1 - 1 of 1 Posts

3,682 Posts
Discussion Starter · #1 · (Edited)
Softening Aquarium Water
by Sylvain

Discus and riverine cichlids in general require water conditions quite different from their rift lake cousins. These fish prefer neutral (and even slightly acidic) and soft water. There are several methods for softening your aquarium water. The following list contains five methods available for softening your water.

  1. Peat - it absorbs and sequesters calcium ions while releasing valuable organics into the water (humic and tannic acids that will also lower the pH). A very good compliment to RO water, but it won't work well if the buffer is too high. Like carbon, quantity is the key... Both Hagen and Eheim sell peat for their filters.
  2. R.O. Unit - the best option IMO - it produces pure water without salts. Aquarium salt needs to be added to the tank water (which will provide the necessary electrolytes without the hardness). A unit can sell for as much as $400 (it's mostly the gpd rating that determines the price).
  3. Rain Water - only when the pollutions levels and the frequency of the precipitations make it feasible (a modified plastic garbage can could filter out dust and debris and provide usable water). I can't recommend this method because even the most pristine environments are not so pristine anymore.
  4. Selective ion exchange resins - basically the water softener pillows that removes calcium/magnesium ions by adsorption (you shouldn't use the tap water types). Some will also remove toxic metals. Strong acids are required to recharge them - not very practical, in my opinion.
  5. Driftwood and Duckweed - not very effective - the wood acts a bit like peat (adding valuable organics), while the Duckweed can use some carbonates during photosynthesis.

I know Aqua Pharm and Kent both make pillows. The science behind them is sound, but they won't be cheap or practical to use on large tanks.
1 - 1 of 1 Posts