Can I manually dose Kalkwasser to increase pH?

[GuppyHJD]

Question:
Can I manually dose Kalkwasser to raise my pH? My calculations show to raise my ALK from 9.6 to 9.65 (only .05 a day), I need 198ml added to the tank. Either a drop ever 5 seconds or ?? ml ?? times a day?
I am aiming to raise my pH to 8.2.
Situation:
I have a 120g tank, with sump and skimmer. Lights might not be strong enough - two Noopsyche K7 Pro II.
The tank has been in operation for 8 months since the cycle.
The tank has 10 coral frags, one BTA, six fish.
The tank was setup with dry rock, special grade aragonate sand. The water is RODI with Fritz blue salt. I am changing 30 gallons every 4 weeks.
Temp 78.5, Salinity 1.025, pH 7.8, ALK 9.5-9.6, Calcium 470, Magnesium 1470, Nitrate 25, Phosphate .17
I am changing the filter socks every third morning. I am emptying skimmer cup every 4 days.

Concern:
The corals are not growing, some are shrinking.
I tested the pH with outdoor air vs inside air - it shows I do have high CO2 in the house, but cannot get outside air to the skimmer and it would be very warm air (was 98 degrees outside today). I am considering a CO2 scrubber.
The tank has had Dinos (cleared), Cyano (cleared) and now some black/dark blue algae on the sand.

What am I doing wrong?
Thank you

 

[Randy Holmes-Farley]

I would not be sure the coral issues are pH related, but you can certainly manually dose kalkwasser.

However you dose it needs to be slow, so purely manual will mean many small additions spread out.

 

[arking_mark]

I have found that I get a better more stable boost with a steady Kalkwasser drip. If you don't want to use a doser, you can go low-tech with a gravity drip.

 

[GuppyHJD]

I have found that I get a better more stable boost with a steady Kalkwasser drip. If you don't want to use a doser, you can go low-tech with a gravity drip.

Thank you. I am going to try to configure a gravity drip. My ATO is a gravity feed. I am running out of space under the stand.