HELP: Purple leaf tips and edges, dark purple branches and leaves dieing

I've always had problems knowing when to feed this plant with my guano nutes (10-10-2) as my nutes don't say how often i should feed but no matter how often or little i feed it it keeps getting worse.

This plant used to be perfectly fine:

I figured it must be a soil pH problem as the run off was at 5 and the water going in is 7 so i dressed the top of the soil with 3 teaspoons of dolomite lime and mixes a teaspoon into the water then i flushed with about 12L of water.

The plant is still growing slowly but is this the problem solved?

Can anyone tell me what specific deficiency is casing the purple
and PLEASE TELL ME HOW OFTEN TO FEED!

 

Maybe i'll just go back to using my old blood and bone nutes (8.3.6)
They don't sell foxfarm products in my country.

Should i still start off at 1/4 strenth? i mean it's a deficiency and this plant is well approaching two months with the last month being slow growth.

I'm just hoping none of this will stress it into a hermi as it was a feminized seed.
Only female preflowers atm so hopefully i'll be good.

 

It's been flushed with 12 liters of water a couple days ago. I'm not flowering yet until these problems are sorted but yea i know what to give in flower.

 

They don't sell specific cal/mag supplements in my country. The dolomite lime has cal/mag in it though and i added that a few days ago. The plant seems to have perked up slightly since i added the blood and bone but i still don't know if problems are solved.

 

Well i don't really have the funds to be going all out on supplements.
We do have quality local products and stuff from Australia here though.
but the dolomite lime should take care of the cal mag def if it
is infact a pH lockout.

One thing i have noticed is that the top leaves were canoeing upwards to
the point where each side of the leaves were touching.
There is no canoeing now but that could just be down to them
getting bigger.

The pH of the water is 7 and the pH of the soil run off was 5 so the soil must have had quite a low pH which is why i added the dolomite lime.

If the problem continues it must be a conspiracy.

 

Runnoff was 6 right after i put the dolomite lime in. I flushed after i put the dolomite in so it would act a little faster. I'll check the runnoff when it needs another water. I don't have a soil pH tester but it should be fine with the dolomite.
Dolomite is a slower soil buffer than other limestones so it'll probably take a while to neutralize the soil pH.

 

2 days after adding the blood and bone with more K than the guano, the plants new growth has almost got its green back overnight, the leaves are flattening out and i noticed the most growth it has had in a while this morning too. I'll give my crappy guano (10.10.2) nutes to my brother for his tomatoes or something.

Before:

After: (leaves are much darker in real life than
they are on cam)





thanks. Now i can grab me a bigger pot for flower