I don';t know how your dealer recomends setting up the D-1 spa witht eh vision cartridge but I'll tell you what works best here in central NY. We have our customers initially add a stain & scale / metal control when there is about 2 inches of water in tub while it's filling. Then wait two days and add 2 oz of dichlor to sanitize the source water, 30 mins later add 2 oz of non-chlor shock (MPS) to help alleviate the chlorine odor. Wait 24 hrs and then test the spa water (bring sample into the store to be tested), and make the proper adjustments to Alkalinity, pH, & calcium hardness. Aftwer the water is balanced we have them add the vision cartridge. The vision goes on top of the filter that doesn't have the floating weir. Now in our experinece with the vison and also Nature 2 cartridges the pH in your spa will almost always be around 7.8 or higher, due to the fact that the cartridge itself(the minerals in it to be exact) has a pH of 7.8. It should also be noted that if you use a non-chlor shock(MPS) over the course of a week or two it will lower your alk. AWe recomend to our customers that they keep their spas Alkalinty on the higher side of the scale, more towards 150-200ppm. This helps maintain your pH at 7.8-8.0 and also gives you more leway when shocking with MPS. Now please be aware that when and if your pH goes higher then 8.0 your spa WILL scale. I hope this helps you out, if you have any questions please feel free to ask me, but keep in mind that it is pool season here in NY, so my response time will most likely be delayed.
Jason,
Store manager for a D-1 and caldera Spas dealer
