Originally Posted by SinCrisis
well i cant actually test my water, but i know that my softener system takes out most of the hardness for sure since i refill the salt all the time >.<. I heard that crushed coral sometimes has things absorbed in it like salt that can be bad for a freshwater tank..? The tank i plant to set up soon is a 1.5g betta tank using soil and lots of plants, also sorta for the low-tech aquascape contest, but the tanks modded so i think i might be disqualified from that. I want the hardness cuz i want to introduce trumpets to the tank to help turn the soil and keep it clean. I figured i could buy a box of chalk and crush up ~1/3 of 1/4 of a stick and mix it into the soil so itll dissolve somewhat faster and most of the calcium will stay under the sand layer for the snails and plants.
Perhaps if you were to use water from outside faucet that is not hooked up to the softener system or use water from someone who does not use softener system, you would not need to add anything to the tank. Some water softeners remove the calcium and magnesium and replace these with sodium salts.
Domestic water softeners do remove calcium and magnesium which causes deposits in sinks and tubs and on fixtures ,but often times the outside faucet that folks use to water the grass is not hooked up to the softener system and the water would have the hardness you desire. You would only need to heat it before use and add dechlorinator.
In any event You really should use a test kit for pH,GH,KH and if you are going to use substance such as chalk . or other water altering substances you should do it in separate conatiner and test after a day to see what effect it has on the water rather than adding substances to a tank holding fish. This way, you can be sure and make up the correct amount each time you need to do a water change and fishes are not negatively affected by sudden change in water chemisrty.
Not trying to be negative or combative, but rather maybe help you to make things easier. The LESS you addd to the water or aquarium, the better for fishes and easier for you.