leaves with rusty tips and edges

[Biograss]

I'm in the 5th week of flowering and for 8-10 days one of the 5 plants has rusted leaves on the edges and I can't stop it. I use an organic fertilizer from biobizz and the ph of the water is always at 6-6.2. and with another plant it seems that the buds have stopped growing and seem to have many more leaves and it grew very big and I had to tie it up. I planted 2SUPER SILVER HAZE,2GLOOKIES and 2GELATO and when I moved them I forgot to write what they are

 

[Creeperpark]

I'm in the 5th week of flowering and for 8-10 days one of the 5 plants has rusted leaves on the edges and I can't stop it. I use an organic fertilizer from biobizz and the ph of the water is always at 6-6.2. and with another plant it seems that the buds have stopped growing and seem to have many more leaves and it grew very big and I had to tie it up. I planted 2SUPER SILVER HAZE,2GLOOKIES and 2GELATO and when I moved them I forgot to write what they are

What kind of water are you using? Tap?

 

[Biograss]

What kind of water are you using? Tap?

Yes and I m fix the ph with organic ph-down(6-6,2)

 

[All Cacti Are Beautiful]

Any idea on ppm/tds?

 

[Biograss]

Any idea on ppm/tds?

No it’s first time growing.i use a marshydro fce-3000,tent is 90/90/180,vevor inline duct fan 205CFM