What's wrong with my calcium?


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I've had my tank up for about 8 months now and my calcium/alk is driving me crazy. My calcium has always been over 500, usually around 540. My alk is always low despite using Kent super buffer. When I first started the tank, I used a product called BioCalcium by Tropic Marine, I have dripped Kalk off and on. I have not used any kalk in the past 3 weeks. Yesterday my calcium was 520 and alk 6 dKh. I have done water changes without any benefit. I have a DSB of aragonite, most of my rock is aragocrete. My coralline algae started grwoing about 2 months ago and then suddenly stopped and bleached out. I have also noticed a fuzzy brown algae growing on the sand, but only in areas exposed to light. I added Phoszorb to the sump about a month ago and run carbon in the sump as well. Anybody have suggestions or ideas? My LFS says that high calciums are common the first year as calcium leaches out of the sand bed, but I'm afraid that this is causing my corals to just not thrive. Help me.:doh:
If your Ca is High..and yours is.. your Alk should be low...it is directly porportional ... Calcium of over 400 is best, 500 I guess is OK but not perfect.., Alk of 5 is perfect.
yeah 6 dkh is too low. I'ld say do a water change, check levels, and only add alk, no calcium. Test again to see where levels are. To bring calcium down, you must equal out the alk.
glxtrix wrote: also, what is your magnesium at?

I don't have a mag test kit. I have been trying the water change thing though. My fresh ASW has a calcium of about 400 and alk of 8 dKh, so I figured something weird is going on. Is there any harm in driving the alk up with super buffer?
the only harm i could see is it directly effecting your Ph, or driving your calcium down.
What effect would it have on the pH throughout the day? I ask cause my xenia expands and pulses beautifully during the NIGHT but then shrivels up during the DAY. Another reason I think my tank has gone crazy. Actually, I've been thinking about getting a pH meter cause I think I may have some bad pH swings with the abnormal calcium and alk.
yes that you will, Ph is effected with alk, thats why you need to be careful how much you add cuz you could drive it way up.
I don't know what dKh is but. ALKALINITY in meq/L should be around 5. KH is is around 12.5

Natural seawater has a KH of 8 or Alkalinity of 2.9...If we are talking the samething. Forgive me.

So go from there
dKH = Degree Karbonate Hardness (German origin, measure for carbonate hardness alkalinity)

Its the same thing as saying KH or meq/L all depends on what test kit you have depends on what it reads. Salifert reads meq/L and dKH (KH), other test kits like tetra or what ever really only say dKH (KH).

So technically you are right in saying 5 meq/L is good for alk, a lil high in my oppinion, but that would equal to about 14.1 dKH. All according to Salifert that is.
Thanks reef1973, I think you're right, Biocalcium is calcium chloride. I didn't realize that super buffer would be bad, I did a big water change last night and the tank looks a little better. I will retest my water and see what it shows.
OK, here are the latest numbers: alk 8.6 dKh and calcium 460. This is the first time that my calcium has been less than 500! Everything still looks the same though, but I'm glad the water changes have started to normalize things.
I just happened to have some biocalcium on hand and decided to add it. That was before I bought a calcium test kit, now I realize that I was adding too much of it....way too much of it. I restarted the kalk drip tonight and will be leaving things steady for at least the next week (I'm going on vacation). I will recheck my parameters tomorrow.