Sugar leaves turning white!!!

Hey guys, I need a little insight here. I got dome sort of mango strain 6 weeks in flower and everything has been looking killer until last night I noticed a bud that looked like it was getting bud rot or light bleaching. It was a top on a lower branch and I notice other sites on the plant the sugar leaves on the bud is turning brownish on the tips and along the edge on thier way to turning white. Not sure whether to flush it or what. I did notice my night temp got down to 58 cause I forgot to plug my heater back in but not sure thst would cause this.
I have been using Botanicare nutes and its in happy frog soil,no other supplements. I attached a pic of how its starting on another bud and im sorry about the HPS light but I could turn em off for a pic.

how many mls per gallon are you mixing for your botanicare ?
and which botinicare products are you using

I think its nute burn.. I would flush

test the ph and EC/ppm of a sample of waste water coming from the bottom of the pot

the low temp drop didn't do it

Better pic

botaincar has bloom, bloom soil, CNS17, and some dry salts

Sorry guys ,didnt see anybody replied. I have been using the bloom soil at 20 ml/gal, Liquid karma at 5 ml/gal,and cal magic at 3 ml/gal. I havent noticed anymore turning white ,but that particular plant has a lot of burnt tips but dont seem to be getting worse.

this(above) is what I would do if I was you

lower your bloom for soil
pick up some pro grow
get some Epsom salt from the grocery store

dose per gallon
9ml bloom soil
3ml grow pro
5ml calmag
0.2 grams of Epsom salt per gallon

to achieve
74 N
48P
125K

N is slightly more than half of K

potassium to calcium to magnesium ratio
3:2:1

this is what your currently feeding at 20ml/gallon plus the calmag

the K is so incredibly high is going to lock out calcium and magnesium

the over all active elemental ppm is 495 which is high and likely to cause burn

the P is extremely high also which can cause issue with iron and zinc

if you cut the dose in half the P and K would work but then your N is too low

I didn't figure in for the liquid karma... I don't think it has enough of anything to change the numbers much

the NPK on the bottle are very low I pressume

the formula for the
dose per gallon
9ml bloom soil
3ml grow pro
5ml calmag
0.2 grams of Epsom salt per gallon

those are some very good looking numbers for pot... you be happy

if you like a little more N in your formula you could mix it like this

and more N again..starting to see the pattern yet?

if you want to leach N as you go into deep flower you could use all three

first 2 weeks of flower mix the 6mls of each with N at 90
week 3 and 4 mix the next one with 7mls and 5mls reducing N and raising P

week 5 and six feed the first one reducing N to 74

and if you want to reduce N even more I can make you another for the last 2 weeks of fower

itll be the next pic I post

last 2 weeks of flower you don't need the grow
12mls per gallon of the soil bloom alone is good

high P high K low N

sorry there all out of order