Water to soft.

[Tankfull Tropicals]

I know I should not complain but my tap water is to soft. From tap it is 6.5 ph and no readable carbinates at all. Very close to rain water and does not change over the seasons. I would like to know what others do to bring UP the hardness.

[Fern]

I use a scattering of crushed coral or a few shells to bring it up and wood to bring it down, I do it all in tank and naturally, safer and easier!

[TwoTankAmin]

Hardening Your Water (Raising GH and/or KH)
The following measurements are approximate; use a test kit to verify you've achieved the intended results. Note that if your water is extremely soft to begin with (1 degree KH or less), you may get a drastic change in pH as the buffer is added.

To raise both GH and KH simultaneously, add calcium carbonate (CaCO3). 1/2 teaspoon per 100 liters of water will increase both the KH and GH by about 1-2 dH. Alternatively, add some sea shells, coral, limestone, marble chips, etc. to your filter.

To raise the KH without raising the GH, add sodium bicarbonate (NaHCO3), commonly known as baking soda. 1/2 teaspoon per 100 Liters raises the KH by about 1 dH. Sodium bicarbonate drives the pH towards an equilibrium value of 8.2.

From http://fins.actwin.com/aquariafaq.html

[Fern]

Ya.... shells and wood is the safest way, no yo-yo effect from them.