water too hard?

[adam & jeanne]

Ive just gotten my first order of live rock and its got lots of life on it. I believe some of it is probably small corals. Ive decided to go ahead and upgrade my lighting to support the corals. My question is:
I measured my carbonate hardness the other day and it was 13 dKH. This was high according to the tetra test kit I was using. Is this too high? What will it effect and how does it effect it? How do you go about softening the water if needed?
55 gal
45 lbs. LS
45 lbs. aragonite
30 lbs. LR
2 penguin 330 biowheels
2 penguin 550 powerheads
1 ebo-jager 200w heater
6 damsels(to be leaving soon)
in the process of cycling right now, nitrites are dropping as of yesterday

 

[kris walker]

No, that's not bad. Many people keep their alks higher than the natural seawater alk (7-10 dKH) to keep their small tank more stable. The ocean is very stable because there is so much water there and it all circulates all the time. However, your tank is miniscule compared to the ocean, so a minor change can lead to a significant impact, say in pH. So to compensate, people sometimes keep their alk from 7-17 dKH.
kris