Soft water problem

[Bullgod68]

I recently (3 days ago) set up my 55 gallon tank again. I used a layer of laterite covered by smal gravel to a 3 inch depth. I then added an assortment of fast growing, hardy plants that cover about 60% of the tanks footprint. Also added a used sponge to my aquaclear filter from a fellow hobbyist. I added the recommended amount of Cycle to the water and let it run for two days.
Today I added 15 guppies, 10 zebra danios and 4 cory cats. I tested my water and everything is fine except for the water hardness. The area I am living in has very soft water (<20ppm GH and close to 20ppm KH) and the water in the tank also reads very soft.
My question is how does one go about safely raising water hardness, and will raising it affect other water factors?

PH - 7.4
Ammonia - 0
Nitrite - 0.1
GH - <20ppm
KH - 20ppm

[Hebdizzle]

those paramaters do not seem out of the ordinary.

[NJ Devils Fan]

Yea, why do you want to change anything?

[Pink Pat]

Bullgod68,

I agree with the other two replies. Your water parameters seem to be quite good.

The GH is a measure of calcium and magnesium and is important only to your plants. Fish care almost nothing about GH. It only matters to the plants if you have a very low GH (because these are essential nutrients for plant growth).

KH is a measure of carbonate and bicarbonate ions in the water. It is a measure of how resistant you water is to shifts in the pH. A measure above 3 is 'good' and 4 or more is quite satisfactory. Your measure of 20 is quite good for your needs.

HTH

PP

[Bullgod68]

Ok, from the literature that came with the test kit indicated that both the GH and KH were quite low in my water. I have always lived in hard water areas and have never dealt with water this soft.
Thanks for the replies, lots of great info on these boards.

[famman]

20 ppm of KH is about 1 degree of hardness. I think that is dangerously low and will subject you to pH swings as well as reduce the amount of C02 you can dissolve in the water for your plants.
Read this for more than you ever wanted to know about pH and KH.
http://www.tomgriffin.com/aquasource/hardwater.shtml

You might try adding sodium bicarbonate to bring KH up to a minimum of 2 degrees, maybe 3.

[Bullgod68]

Thank you for the helpful information, I too thought that water as soft as mine would swing my ph balance wildly.
I'm heading out to by some sodium bicarbonate today, hopefully this will bring the water into the acceptable hardness range.

[Bullgod68]

After reading some articles on raising water hardness I have a couple questions.
Is adding limestone to my aquarium better than using sodium bicarbonate?
Could someone explain in parts per gallon how much limestone/baking soda to safely add to a 55 gallon tank to raise the hardness to an acceptable range?

[famman]

You may have to perform an experiment or two. Crushed coral is another popular method of gently raising KH, I don't reccommend using limestone.
good luck
:)

[superjohnny]

Baking soda will do the trick as well. I think I use calcium bicarbonate to raise my water hardness.

Make SURE you raise the KH before injecting CO2. KH is a measure of the buffering capacity of your water. Without a buffer adding CO2 will cause your PH to crash... literally. When I first added DIY CO2 my PH went from 7.0 to ~ 5.0. How my fish lived through it is beyond me.