Kalk before corals?

[Footbag]

I just recently finished my cycle on my 45g (60g total)cube and tested my calcium and KH for the first time today. Used salifert tests.

Cal 295
dKH 8.15
PH 8.2.

I didn't test earlier, but given those results I know I have to raise my Cal. I don't have any corals in the tank, I am getting some zoanthids next week. But I don't think they use calcium, so all that is consuming it is coralline. I do have some good coralline growth for only being a month and a week in.

Should I consider adding Kalk to my topoff? I evaporate about a gallon a day, and use a powerhead/float switch to top off. It adds about a cup of water before triggering the float.

I have and plan on using a Calcium reactor, but one of the valves needs to be replaced and I remember it being a major PITA. Would Kalk be a good temporary solution? How much should I add for coralline alone? I remember having good luck with Kalk in my last tank until it just couldn't keep up.

[HighlandReefer]

Which salt mix are you using? What is your salinity and how do you measure it?

[Footbag]

Which salt mix are you using? What is your salinity and how do you measure it?

Thanks for the quick response...

I'm using Instant Ocean, my Salinity is 1.024 and I used a Refractometer.

[HighlandReefer]

Coral and coralline algae use 1 dKH of alk for about every 7 ppm calcium.

IO mixed at 1.0264 salinity will have about 400 ppm calcium and about 11 dKH per Billy's testing.

So unless you have been adding an alk supplement it seems your calcium is much lower than it should be. I would suspect an old alk kit over a year old which is not reading correctly. I would get a second opinion on your alk kit.

I would increase your salinity slowly up to 1.026-1.027 which will provide better parameters than 1.024 while using IO.

I would increase your calcium level using calcium chloride to your desired level. Then you can use kalk water mixed to start at 1 teaspoon per gallon of rodi water. You will have to adjust the amount of kalk you add per gallon of rodi water to meet your alk demand. Calcium will follow suit. ;)

[HighlandReefer]

Kalk water will become saturated at 2 teaspoons per gallon. So adding more will not benefit you unless you decide to add vinegar to it. ;)

[Footbag]

My ALK kit is 3 years old, but so is my Ca kit. So you may be right and I think I need two new kits.

I'll also begin the process of raising my salinity, but won't touch Ca and ALK until I can test it.

Thanks for the help.

[HighlandReefer]

Sounds like a good way to go. ;)

FWIW, salinity should not be raised by more than 0.002 per day. Replacing salt mix for your top-off water is the safest way to increase salinity.

[Footbag]

Sounds like a good way to go. ;)

FWIW, salinity should not be raised by more than 0.002 per day. Replacing salt mix for your top-off water is the safest way to increase salinity.

In the process of mixing up some SW for top off as I type. From past posts it looks like it will take about 6-10 days if the water is 1.026.

Thanks again.

[HighlandReefer]

Your welcome.

Happy Reefing