Calcium chloride alk question

[smarrone]

Randy,
About 6 months ago you helped me w/ a low ph problem in new saltwater mix. Now I can get new saltwater to mix to 8.2 ph and alk about 11.2 dkh at 1.023sg. You told me to adjust my ro/di ph first w/ a little Kalk (about 1/64 tsp/gl) before adding the salt. I was one of many that was getting high alk trying to adjust ph w/ buffers. No more buffers for me. Now, I've just talked to Leng at Ecosystems and he said for corals I should get my alk down to 7-8 dkh. He said I could do this w/ calcium chloride or phosphate remover. My question for you is: Should I stop using Kalk and somehow use calcium chloride (have never used it) to get my water right? I don't know how I can get my ph to stay over 8 and yet keep that low (7-8 dkh) an alk value, or do I just add calcium chloride seperately to the tank to maintain ph and lower alk? Any suggestions are appreciated.
Thanks,
Sam

[Randy Holmes-Farley]

I recommend 7-11 dKH for alkalinity, and plenty of aquarists keep it in the 10-13 dKH range.

What is the alkalinity in the actual aquarium?

Are you adding anything to the aquarium itself?

What is the calcium now?

[smarrone]

Randy,
Right now this is a bare 100 gl tank, will not stock until lighting arrives this week. All that's in it is saltwater made from IO salt, it's just circulating. Water parameters are 8.19 ph, calc 330 ppm, alk 11.6 dKH, 1.023 sg. No supplements used except kalk when I mixed the saltwater.

Thanks,
Sam

[Randy Holmes-Farley]

I'd bring the calcium up to 420 ppm (matching NSW) with calcium chloride, and then it will be fine. I wouldn't worry about the alkalinity.

This article may help you:

Reef Aquarium Water Parameters (a summary general article)
http://www.reefkeeping.com/issues/2004-05/rhf/index.htm

[smarrone]

I gather I should mix salt as I'm doing now and then add calcium chloride to the tank?

Thanks,
Sam

[Randy Holmes-Farley]

Yes. :)

[smarrone]

Randy,
I've been reading other calcium questions which lead me to one more question here. Would it be better to mix calcium chloride period when I make new saltwater and not use kalk anymore? I've seen in the forum that some mix new saltwater using calcium chloride. What would you recommend for reef setup?

Thanks,
Sam

[Randy Holmes-Farley]

I would only recommend that if the new salt water had significantly less calcium than you keep in the aquarium.

[smarrone]

Randy,
Will calcium chloride raise ph like kalk? I'm going to mix some up tonite but can't stand the wait! I'm hoping to make a trial gallon of new saltwater w/ a ph of 8.1 or so and alk of 7-8 dKH. My plan is to dose 1 gallon of ro/di w/ calcium chloride, amount will be monitored by ph meter, then add salt hoping to achieve lower alk then when I dosed w/ kalk, do you think I have a chance?
Thanks,
Sam

[Randy Holmes-Farley]

No, calcium chloride has no impact on pH of marine aquarium water.

If you add too much at once (driving calcium well above normal values), you may end up precipitation a lot of CaCO3 from solution. So be sure to use one of the calculators to not over do it:

Andy's calcium calculator
http://www.andy-hipkiss.co.uk/cacalc.htm