Phragmipedium Nicolle Tower purplish blotching help

[Ray]

There is nothing wrong with that plant!

My Sorcerer's Apprentice lives out on my deck up against the north wall of my home, so never gets any direct light, and it has done the same from time to time. The plant has red in its genes, and that'll sometimes be shown in the foliage.

Magnesium deficiency emanates as pale green to yellow, not purple. If you do have a mag deficiency, as much as a tablespoon of Epsom Salts per gallon isn't going to hurt anything.

I am curious about what "150 ppm MSU and cal-mag" truly means. 150 ppm TDS or 150 ppm N? Which MSU formula? Cal-mag formula? How much of each per gallon? Based upon the original statement, I think you could be either underfeeding in general, or overdosing the calcium.

[Clawhammer]

I grow both orchids and succulents under grow lights and coloring up is one of their defense mechanisms when receiving bright light. I agree with Alice, color is a good sign of sufficient but not too much light as long as there is no burn.

[JennyNE]

So I wish I knew how many parts of N. But again I’m new and just figuring this out. I use a TDS meter and after adding the RePot Me MSU fert I it reads about 120ppm. Then I add about 30ppm general hydroponics calmag. I’m about done with the repot me fert and won’t be buying more. My next goal is to really figure out how to better measure fertilizer. But I also worry I’m not giving enough. Since I posted my first post a second bud is about to open and I got one bottom leaf with a little browning on the leaf tip. And both bottom leaves look a little yellow. But just slightly.