What is wrong with my tank?

[ZoaMaster09]

Ok I have done multiple tests now with API Test Kit and my calcium is super high....it is at 36 drops my ALK is at exactly 8 drops and the Ph is is low 7.8.
I have tried to raise ALK thinking it will decrease calcium to appropriate levels but so far I have not seen a change.
I recently added a phosphate reactor could that be a reason for high calcium concentration in my tank?

[zigzag1]

IME high indoor CO2 levels make my tank drop .3 pH in the winter months. If you have a newer home that is well insulated and sealed up, the effect may be amplified. I've recently seen a big change to this trend by adding a CO2 scrubber which uses soda lime pellets. Now I'm back to a pH around 8.2 - 8.3 even at night. Even though the pH value is higher, I've not seen a huge difference in the tank appearance. Many direct to maintain the proper Ca and Alk values and not sweat the pH value as much. This suggestion seems to match my observations also. JMTC & GL!

[reefgeezer]

Adding alk will not directly lower calcium unless you drive the alk so high that you have a precipitation event. That's not a good plan. I'd let the calcium fall slowly and add only enough alk to keep it in the low normal range. Once ca and alk are normal and steady, then I might fuss over the pH. 7.8 isn't terrible.

[Reef264]

Do you dose calcium?Is it just naturally that high, as if by your salt mix?by my Calculations your Calcium Levels are sitting around 720ppm!That takes some dosing to achieve that!

[ZoaMaster09]

I'm using coral pro salt and yes I did dose calcium a few times last year in December when I noticed my Dendros were dieing, but in my opinion it wasn't a heavy dose or a constant dosing neither. I'm just a bit confused, I always thought that failure to maintain P.h around 8.1-8.3 will kill your live stock (corals) or at very least they will not grow proper so for me to read you saying 7.8 is not bad, its surprising.
So I have to do water change soon, will a 30% (instead of a 20-25%) water change help bring things on check?
So far these are the corals that I have seen are having a hard time in my tank.
Colony of Dendros, Purple flower pot, everything else is ok.

[Reverend Reefer]

i had high ca once, then i started dosing mag weekly and the ca levels dropped to a more normal level. someone on RC suggested it, if i remember correctly, my ca was high because my mag was low, limiting how much of the ca could be used up.