New tank, consistently low parameters, advice going forward please

[LisaRPG]

As the title says I am frequently recording low parameters, but pretty consistent (see graph photo), I have mainly Zoas and a few lps (see photo) all Zoas are producing new growth, the most miserable coral is the little frogspawn middle of picture.
So my question is; can I be doing more? Should I fiddle when I seem to have growth? If yes, I understand one thing at a time is best- what would be your suggestions?

Tank: waterbox 20
5 months old
1st chamber runs a floss cup, middle chamber bag of seacham seagel and a bag of bio matrix and heater, final chamber standard pump and ato.
temp runs at 80
AI prime 16
Carib sea life rock
Carib sea live sand
1 firefish
2 red leg hermit crabs
3 narcissious snails
1 conch
2 turbo snails
Parameters are below and taken before the 10% weekly water change, salinity seems to naturally sit consistently at 1.023-1.024, red coral pro salt mixed with own TDS tested RODI water.

I feed once daily a few grains of marine pellets pr 1/4 cube of frozen mysis or brine shrimp, anything over that and I seem to get an ammonia problem even though 1 fish.
CUC are doing a good job of sand and rock work I am manually removing back wall algae.

Hopefully I’ve provided enough information to get some sound advice- many thanks

 

[Tamberav]

If you mix to 1.026 instead of 1.023 then your alk/ca/Mg will also be higher.

 

[Dom]

ALK and Calcium are low.

I keep my all in the 8.5-9 range.

Calcium, I keep at around 410-440.

Bring up your salinity and the other numbers will likely come up.

 

[Koh23]

Ca and mg dont worries me for this corals, but seeing alk so low does....

Something is off, red sea coral pro have elevated alk,mg and ca levels, with this type of corals, and regular water changes, its kinda impossible to have these values so low.

 

[LisaRPG]

Will mixing higher in the 10% weekly change be a) enough to make a difference and b) be gradual enough to not cause a swing?

 

[Dom]

Will mixing higher in the 10% weekly change be a) enough to make a difference and b) be gradual enough to not cause a swing?

To raise your salinity, just do water changes making sure your new water is at 1.026. After a few water changes, your number will come up and level off where it should be.

Low salinity is effecting your other numbers.

Get the salinity right first and see where your other numbers land.