25 lagoon with tropic marin pro reef, low alk, high cal and mag help with dosing

[Realamerican13]

Hey all, I have a 25 lagoon AIO with 10 LPS corals, a few softies and 4 fish (2 clowns, possum wrasse, helfrichi firefish). I have approx 20 gallons of water in the tank and have been doing 3-4 gallon water changes weekly since tank was set up (3 months ago). I use tropic marin pro reef salt and mix to a salinity of 1.025. Test results via red sea test kit and hannah checker for alk on fresh mixed saltwater were as follows: Alk 7.3, calcium 475, magnesium 1440. I then tested alk half hour after water change and got 6.3. I have been testing daily this week to try and dial in a dosing regiment. I would like to give Tropic Marin All for Reef a shot but im skeptical due to the Alk dropping and calcium/mag seems to be remaining stable. Ph has been a stable 8.1. Any thoughts as to why corals are consuming alk but dont seem to be consuming calcium? Dosing recommendations? thanks.

 

[EW_Fish]

What is your ALK in tank before water change?

 

[Realamerican13]

It was testing to 6.4 with Red Sea, just got the Hannah so I used that.

 

[EW_Fish]

Those small water changes aren't going to bring your ALK up unless the Fresh batch is like 11dkh. I would try raising your ALK up to 7.5-8DKH (manually) then maintain it with water changes if possible

I consider ALK at 7.3 on the lower end and small room for error

 

[EW_Fish]

 

[Realamerican13]

Agreed, the salt is designed to have alk on the low side, at 1.023 salinity it should be 7 dkh, I’m going to bring it up to 8, I have all for reef but don’t want calcium/mag to go too high

 

[EW_Fish]

All you need to do is dose ALK and no more then 1DKH a day rise. Once you get to your desired level you can maintain it via water changes or dosing.