The last feed was 16 liter water with;
20ml Biobizz Grow 
20ml Biobizz Bio-Heaven 
20ml Biobizz Acti-Vera 
20ml Biobizz Bloom
20ml Biobizz TopMax
Also I correct the ph to 6.5. (With Biobizz ph-)
A few plants have some yellowing tips. I thought this is over feed. Please your opinion!