We've talked about this product for decades. Here are some of my comments from other threads:
The claims are ludicrous. Even if it did something useful, I would never support this company due to this sort of false advertising.
"Sea-Lab #28 restores and maintains the concentration of calcium, strontium and all trace elements at the same levels found in the sea, automatically. Formula #28 always works, and cannot be overdosed. This is not a slow-dissolve or time-release product. It dissolves only to replace depleted elements."
Well, I'll just reiterate that no product can do what these claim.
You may succeed in spite of them, but I strongly recommend taking a different approach where you actually have some control over the final alkalinity and calcium values attained.
It dissolves, releasing everything in it, at some rate.
It certainly does not do this:
"Sea-Lab Formula 28 is a mixture of naturally occurring buffer compounds that maintains natural ocean concentrations of calcium, strontium, and all 15 essential trace elements. "
"As elements are depleted from solution, Formula 28 delivers exactly equivalent amounts to replace them."
Curiously, it makes no mention of magnesium at all. Their "product analysis" is just a list of concentration of SOME ions in seawater. If you believe their list of ingredients, it releases those over the time it takes to dissolve. . By the time it has dissolved, it has released all of these:
Bad product then, bad product now.
it makes no more sense than to claim adding 2 ml of mystical product A and B to any reef tank every day will
“maintain natural ocean concentrations of calcium, strontium, and all 15 essential trace elements.”