In Need Of Help!

my slh started off perfect through veg gave them 4 weeks got them to about 3 an a half foot then turned the lights they were beginning to show sighns of being over fed so i knocked a few feeds off,then i hit problems my ppm shot up to 36 indicating i had to much nutes in the water (using bud blood i wouldnt recomend its sh*t)then from the bottom my leafs started to go brown from the middle the tips the sides and worked its way up the plant i flushed my res and got my ppm down to 20the bottom leafs have all sorted them selfs out and are very healthy again and branches coming off,but the top,s of my 4 plants look badly burnt or nute damaged iv got 4 slh in 10ltr pots in a 4 pot wilma system using pk13/14 canna,canna boost.and stopped using my atami nutes.running under a 600w hps ultra spectrum.how is all this going to affect my yield and quality of bud im 5 weeks in and they are no bigger than my middle finger hit bk plz peeps

PPMs of 36 and 20?

on which scale?

im from uk an on my truchun theres loads of readings,it might be 3.6 on yours anyway the thing was off the scale cuz 36 is the highest reading and i flushed the 50ltr tank twice before i got it down.i put some bud blood in.a week later put some boontabud in then all the rest followed got any advice to try get my boods swelling?cheers

Try using half strength nutes until growth looks normal and then go back to regular strength nutes and lay off the additives for a while.

thats what iv done for the last 2 weeks,but this canna boost and pk are that strong iv bin putting 25ml of each in every week and it raises the ppm up to high,and its prob not a good idea to be changing to any other nutes

is there anything i can give them to make them swell or is it just a case of seeing if they are able to before hacking them down and starting again?cheers