Water Hardness

[Fish_Newb]

Two days ago I setup a new tank. (Not long I know)

I haven't put any fish in and won't do for a while, but whilst I have been monitoring the levels in the tank, the hardness has gone from 0ppm to around 150ppm in TWO DAYS!!!

Is this normally when a tank first starts up?
I plan to keep a lone male betta in their so obviously this isn't ideal.

Should I resort to using API Water Softner?

 

[OldMan47]

Forget the water softener. You need to start looking carefully at your substrate. It seems that you have something in the tank that is slowly dissolving in the water and making that water get harder. Depending on wjhat5 kind of gravel you are using, it may contain some calcium carbonate or similar substance that can cause an increase in hardness. I would take two samples of tap water and put some of your substrate in one of them. Wait a couple of days and compare how things are going in the samples. If the cup with the substrate in it is much harder than the one that is just plain water you will have found your trouble. People detect this kind of thing more often with pH changes but the same chemicals affect both pH and hardness.

 

[waterdrop]

Yes, completely agree with OM47. This needs to get resolved prior to starting the Fishless Cycling to prepare your biofilter. Its not good having your substrate alter your water chemistry unless you specifically want it to do this and for beginners that's usually not the case!

On a different topic, have you started your "homework" by reading the Nitrogen Cycle article in the Beginners Resource Center?

~~waterdrop~~

 

[Fish_Newb]

Yes, I have read up on that, a lot. I have a '5in1' API Test strip kit (how i found out about the hardness increasing) but I have just purchased their master kit for better readings.
(Found it on ebay for £15.99, half the price of LFS)

I'll do that test with the bottles now as by the time the kit arrives the different bottles will be ready for testing!

If it doesn't appear to be the substrate, is there anything else that could be the cause?

 

[Fish_Newb]

People detect this kind of thing more often with pH changes but the same chemicals affect both pH and hardness.

Just done another test. Bizarrly the GH reads around 60-120 now, and KH at 80. I think the goes to show the inaccuracy of test strips.
The PH however has stayed the same. In what why could hardness be affected without the PH being so as well?

 

[waterdrop]

We usually talk in degrees (german degress technically) if you could calc those (could do it for you but I'm running around..)

 

[Fish_Newb]

Is that dividing by 17.86?

GH-120ppm = 6.7
KH-80ppm = 4.5

Is that correct?

 

[waterdrop]

Right, 17.9 works fine. Congrats - better GH than me, lol. But your KH is right on the border, so that's what's going to get used up and allow your pH to be bounced around. KH=4 is kind of the bare beginning of a little buffer stability, so 4.5 is not much more. KH= 2 or 3 would be worse though.

Now, by running KH tests along with your pH tests you'll be able to put even better data with those bottle tests you're going to do.

~~waterdrop~~