Low Dkh in new system - What happened?

[-Logzor]

I recently setup my new 150g aquarium. I began by adding "new" dry sand, then I filled up the tank with RO/DI water (0 TDS).

Once the tank was full I proceeded to add an entire bucket of seachem reef salt. I did this by adding big scoops with one of those plastic Oktoberfest mugs.

I let the water mix for a few days, checked the salinity, added a few more scoops of salt, checked the temperature, etc. Soon after I added my cycled rock to the tank, then a small temporary LED light.

After 3-4 more days of the tank settling, I tested my parameters of my 1.025 saltwater. Ca 520, great, Mg 1450, even better, Dkh.....5-6..Whaa?

I tested both with my ELOS kit and Hanna checker. Elos read lower, at around 5, Hanna read higher, just above 6.

I don't understand why my alkalinity is so low.

It is because I added so much salt at once? Did it somehow cause precipitation and burn up my alkalinity?

I went ahead and began to add my randy recipe 1, when i poured it in it instantly precipitated. I had to massively dilute it in order for it to not precipitate.

 

[beaslbob]

Bump up the alk to 10 degrees and watch the calcium drop down.

To do Randy's two part you first need to adjust magnesium, cal, alk (in that order) to correct values.

my .02

 

[-Logzor]

Bump up the alk to 10 degrees and watch the calcium drop down.

To do Randy's two part you first need to adjust magnesium, cal, alk (in that order) to correct values.

my .02

I consider my Mg level to be normal/ideal and the Ca to be slightly high. I have no problem running 10+ Dkh, 500 Ca, and 1400 Mg on my existing system.