Calcium/Alkalinity

it seems like everything is running well on my tank (265 gal reef). all parameters are good...nitrates and phosphates undetectable. but i have a question regarding cal and alk...my calcium reading is 255 meq and my alk reading is 11.2 dkh. how do i raise my calcium levels without affecting my alk levels? from what i understand...an increase in one causes the other to decrease. Is this true? i have a cal reactor set-up with effluent drip @ 45 per/min and a bubble count @ 15 per/min. what should i do and how should i do it???? thanks.

 

I think most people will say to bump up your cal. But I have read the same with the alk dropping by cal goin up. Its just part of the trade. You should be checking your magnesium levels, that might be why your cal is so low.

 

You will need a calcium additive, something like this, to boost your calcium levels if you're really that low (have you doublechecked the reading against another kit or at an LFS?).
Bulk Reef Supply - Bulk Reef Supply

First check your magnesium levels, it needs to be 3x your intended calcium level in order for everything to stay in solution. Here's a cheap and good magnesium supplement.
Replacement Magnesium pack (Full Gallon) Bulk Reef Supply

Raising your calcium will only lower your alkalinity if it's too high, some precipitation may occur but it's not a 1 for 1 thing otherwise there would be no way to raise either of your parameters. Here's a good alkalinity supplement as well, of course any will work but these are cheap and easy to use and high quality.
Bulk Reef Supply - Bulk Reef Supply

First get your magnesium in line then start raising your calcium slowly, I only do 50ppm per day usually max. Keep checking your alkalinity and if it drops a little add some alkalinity supplement to bring that up. Just slowly adjust things until you are satisfied with where you are then rely on your calcium reactor to maintain those levels.

As far as you calcium reactor, you need to know the PH in your reactor chamber, the bubble count does not necessarily indicate exactly how it's running, if your PH is too high the media will not be dissolving properly.

Here's an article that goes over how to tune the reactor, in fact it goes over pretty much how to get your system back in balance and maintain your levels pretty much entirely.
A Guide to Using Calcium Reactors by Simon Huntington - Reefkeeping.com

 

thanks screwtape. lots of info. i might have to add some calcium to boost my levels and the reactor maintains it. i have been adding magnesium but i have no test kit for it (on my list). i have korallin mag...500ml...23 bucks!!! thanks for the link!!
the ph in my reactor is high but dropping. its 68.8. i need about 6.7 to dissolve media. have to wait a couple hrs b4 readjusting. but thanks for the heads up!

 

once my magnesium levels are at my target level, does my reactor maintain these levels or do i have to make periodic additions of magnesium like i would for trace elements?

 

This can help you.

 

Most regular media doesn't add mag in calcium reactors, you can use this product, throw it in with the regular media to help maintain magnesium.
ZEOvit ZEOmag Magnesium Granulate - 1kg