I've had low kH in my tank for a while. Adding a bag of crushed coral to the filter fixed the problem for a while but then it went down again. A few days ago it was only at 1 dkH, but after I'd washed and 'recrushed' the coral it's gone back up to 10dkH. I just measured my tap water for kH and it didn't even register! So my question is, can/should I treat the tap water before adding it? I know I've read that baking soda can do the job, but I'm weary of pH fluctuations. Any suggestions?

Chrissy

I use Buff It Up from Goldfish Connection. It maintains the pH perfectly.

but what does it do to the hardness?

What the carbon hardness? It does increase it somewhat. However that really isn't important as the only reason you want a higher KH to begin with is for pH stability. Rick at Goldfish Connection advertises Buff it Up as great at raising and maintaining pH level. And from my personal experience, I don't know how it exactly works, but it works perfectly as advertised.