Phrag. kovachii problem

[Hamlet]

I've had this kovachii for about a year. Bought as a small plant with one growth, it has since produced two new growths and started another one. So it's been doing well so far. Then, suddenly, it started to develop this brown spotting and yellowing on the leaf tips. It was repotted recently and is making lots of new roots, so I don't know where the problems lies. Nothing about the culture has been changed. It is watered frequently. I grow it in a mix of bark, leca and perlite with crushed oyster shells added to the mix. I've never seen this with my other Phrags. Any ideas?

Top of affected leaf:

bottom:

plant:

Thank you!

 

[troy]

Ouch!! I know a stress response happens with this species grown too warm, as far as what that is, my guess would be fungal issue

 

[eteson]

If it is happening only in the old growth do not worry too much, but if it is happening also in the new growths I think that would be temperature issue. As said by troy this species is very sensible to high temps.
What I have learned after killing lots of kovachii plants and seedlings is that the key of success is a BIG drop in temperature during the night and lots of light during the day...

 

[Hamlet]

Thank you both. It's been quite hot here the past few weeks, so I hope it's that and not a fungal issue. It's strange, last summer was very hot and nothing like this happened. I think I'll put the plant outside for cooler nights. It cools down to 12C at night, though, is that not too cold?

 

[eteson]

Thank you both. It's been quite hot here the past few weeks, so I hope it's that and not a fungal issue. It's strange, last summer was very hot and nothing like this happened. I think I'll put the plant outside for cooler nights. It cools down to 12C at night, though, is that not too cold?

12C is a very good night temperature for kovachii