Water Question

[FrostyMountain]

55Gallon tank, up running about 11 weeks.
Have 2 yellow line gobies, two yellow watchman gobies, 2 leather frags, 1 mushroom frag, possible a randalls shrimp, but haven't seen him since he has been in the tank, but no dead carcass yet, unless clean up crew ate him.
My confusion comes from reading the water quality.
I test ammonia, nitrite, nitrate with a API kit, currently Oppm ammonia, Oppm nitrite, 5ppm nitrate.
Test Ph, magnesium, calcium KH/Alk with salifert.
Ph8
Magnesium 750ppm
Calcium ppm
and its this one I don't understand{KH11.2
Alk 3.99)
Those readings are off the sheet that came with the Salifert. Don't know how to interpret these. Can someone tell me how I am. No water quality problems, no algae, all livestock eating well looking good. Thanks

[GimpyFin]

For the alkalinity reading, dKH is the most common measurement people use, which is what the 11.2 is. 3.99 is the same, just measured in milli-equivalents/liter.

[thegrun]

on a side note your magnesium is low, without stony corals that is unusual. Did you follow the testing instructions closely? It is critical that you swirl the solution for 30 seconds before you add the powder.

[FrostyMountain]

Ok so the two numbers in a KH/ALK mean the same thing? What does the KH stand for, and are the readings ok?. Ill retest magnesium, new to the Salifert kit, kind of confusing. If it stays low should I Add magnesium. I use reef crystals and R.o. DI watet, change water 1 to 2 week 10 gallons per change

[nereefpat]

KH = carbonate hardness (k part is German karbonate)

For our I intents and purposes alk and kh are the same thing. The numbers can be in different scales. Think of Fahrenheit and centigrade.

Yes some folks have to supplement a little bit of Mg, although not as much as they supplement Ca and alk.

Hope that helped