Planted Tank Guru
Join Date: Jun 2004
Location: Baton Rouge, LA
I looked at the link, and it appears they were indeed using PMDD as a generic description for dry ferts, rather than the specific PMDD recipe.
With the nearly comprehensive collection of dry ferts you have, you can dose EI, PMDD, PPS-PRO, MCI; anything you want.
I agree with Dundadundun that a little extra magnesium probably won't hurt, and may help if your tapwater is deficient. I used to dose true PMDD, and when I switched to EI I hybridized the recipes; carrying over some of the extra magnesium and potassium in PMDD to EI. Dosed that way for years. Nowadays most people test GH, and if needed, dose a GH Booster after water changes; which supplies extra magnesium, potassium, and calcium. There's a Pennsylvania ex-native sitting next to me, and she says the water was generally quite hard; so calcium probably isn't necessary.