Need advice on 2 part dosing

[Frogger]

The ESV is not a bad product. I used it for about 10 years, bought it from Reef Supplies every year when they had a sale on Boxing Day every year. The ESV is an ionically balanced 2 part meaning that they use NaSO4 instead of MgSO4 making it a true 2 part rather than a 3 part. Quality of the ingredients is likely not as good as the BRS stuff.

I switched because it was too expensive, I started going through 6 gallons of each part every year. If you make your own 2 part or 3 part it works out to be at least 5 times cheaper than the ESV and you can get it in a pinch.

As for trace elements, they are exactly that trace elements, found in your water at microscopic levels you can replenish your supply by doing regular water changes anyways. I am not sure if the ESV has trace elements in it. After using the bulk chemicals for at least 4 years my multiple lab results from ATI have never shown a low level of trace elements or any too much of any other element or substance.