Low alk
 

I tested all my parameters on Tuesday and everything is where it should be except for my alkalinity it's at 6. All my previous tests, the alk was at 8. How do I raise it?
Tests were as follows
Nitrate 0
Phosphates 0
Cal 480
Mag 1250
Ph 8.3
Salinity 1.025
Temp 80

add baking soda (will lower ph - looks like your ph is good so you could either way) or soda ash (baking soda that has been baked for an hour at 300 degrees - raises ph).

look up diy two part reef recipe on google for mixing directions

Baking soda only temporarily lowers pH, and only fractionally anyway. You can buy alkalinity supplements from the LFS specifically designed for aquariums. Some people argue that they aren't any different from DIY recipes, but I've heard the odd horror story from DIY recipes and can't really think of any from aquarium products. For a small tank, cost isn't much of an issue anyway. Your calcium is rather high...are you dosing anything for it? What salt mix are you using?

non reef oriented sodium bi-carbonate can contain aluminum and perfumes.....

This is the first time my calcium has been above 400 and my mag above 1100.

I've been adding k balance, magnesium, strontium and just recently stylo pocci glow. I also have some Kents reef stuff which maybe gets thrown in every week.

I'm using aqua vitro salt, was using instant ocean before but switched bec this had better trace minerals.

I've had amazing growth with my corals but struggling with sps, so that's when I started dosing.

i used to have low alk problems until i started kalk to my auto top off system. since the kalkwasser, i never have problems with low alk.