Help with nutrient or disease problem

[Pommie]

Hi All,

I have three clones that seem to be growing well but have recently started to get browning at the end of the leaves. All three were potted at different times and with different proportions of coir and soil. They are fed once a week on a 25% solution of fertilizer.

Here's a picture of one of the plants,

IMHO, it looks healthy except for the browning at the end of some leaves.

Here's a closeup of the said leaves,

Looking through some of the threads here suggests that it may be Nutrient burn or lack of potassium.

However, all three babies were doing fine a week ago and now all three have this problem so I'm wondering if it's some kind of parasite or disease?

Thanks.

 

[Backlipslide]

The purple stem is concerning

 

[Backlipslide]

Unless it’s genetics, i didn’t think it was because of the green stem towards the top of the plant

 

[Pommie]

Just checked and the donor plant has the same purple stem but seems very healthy so I think it might be normal. The mother is fine but the three clones shared a saucer for a while so the leaves were in contact with each other which is why I'm wondering about parasites and if/how to treat it. Could a Borax mist cause any harm?

Thanks.

 

[Pommie]

An update. I'm now convinced the problem was over watering due to using a mix of soil and coir. Coir can hold a rediculous amount of water.