I always notice that the color on my red monti kind of gets blah looking when my Mg drops...that's a sign for me to check it..lol

I seem to be using 40 ppm mg a day. While alk is 1 dkh and cal about 30-50 ppm a day

Is there a ratio

when you dose, don't forget that the total water volume is different than the 'for every 70 gallon' rule. You must consider water displacement! If you were to take all your rocks out, then add the water volume of your sump as well, you might get a different number. I'm sure you know that, but - a lot of people forget that part!

What are you using to test mg?

I'm using Red Sea. Seems good to me.

I'm use seachem a calculator. So punch I'm my numbers and what is desired and tell me how much to add. I base the calculator on 42 gallons which is what the volume is +\-

That's a crazy amount to be making up in that small of a volume... I dont know if it's just me, but it seems alot.

I notice in my system, as long as I keep my Mg up at 1320ppm, which I add once every 1.5-2 weeks, the other params dKh and Ca are more stable and don't change that much. However, when my Mg drops to 1280, I notice the dKh dropping hard.

My params are listed below. Note, I do dose seachem reef buffer, and seachem advantage calcium. I use seachem advantage magnesium.

Mg - 1320
dKh - 8.0
Ca - 420-440

I have great growth and coloration utilizing this setup. I also use the red sea alk tester.

I'm hoping I find a sweet spot. But it seems seachem a calc may be out. I dosed half of what it recommended and ended up with 1400 ppm


This is from a artical in reef keeping


All magnesium supplements are fairly dilute with respect to magnesium itself, and it often takes surprisingly large amounts of additives to boost magnesium in reef aquaria. For a large aquarium (100 gallons) requiring a substantial boost in magnesium (200 ppm), the amount of supplement may seem incredible (taking, for example, two liters of typical liquid commercial magnesium supplements).

There will be, but it will be specific to your tank.

My tank goes through more Mg then dKH and Ca in a given 24 hour period, I attribute most of this to my clams.

And like was previously mentioned I too find that the brightness of reds and pinks in my system are also impacted by low Mg levels.

Well the clams may explain it. I had 5 sold two and have three left.