When to flush for nutrient lock

my plants are not in a "nutrient" lock position, I am just trying to keep them out of it. I started them at a 300 ppm nute mix and have been raising them by 150 ppm every feeding. now I am at a 1200ppm mix they love it!! What I am curious about is when to flush for the prevention of nute lock? and how often do I flush? also if anyone can help how high ppm can I go without burning them? If anyone can help I would greatly appreciate it......so would the girls!!

if your plants get crispy round the sides, or get food build up growing under the fan leafs and stalk, then you need to flush, you also need to start flushing in the last to week of 12/12. to take the taste of the plant food away from the ween.i think
try to keep pebbles 2" in the bottom of your pots so your food dont build up in the bottom of the pots, have plenty of hole in the bottom too.
good luck and welcome to the site.

how far are you on? how often do you feed. any pics?.

we just transplanted from 1 gal to 4 gal last week, very good they are still in veg but I plan to start flower in about a week. I'll post some pics later tonight. I have watered them once since then, so about every 3 1/2 to 4 days. thanks for the info and the welcome

start a grow j. they help. and if awts wrong people can try to help.if they can.
what are you growing and how many.lites.ect?.

4 x purple urkel under 400 mh and 2 4ft T5 they are in a custom soil mix of 1/2 ff org and 1/2 ff ocean with just the right amount of perlite