Help me save this baby orchid please

[Alvaro78]

Hello beautiful people. The other day I was watering like normal my orchids and this one got some water on the crown (happens) and when I went to remove it I was stupid enough to somehow apply enough force to literally snap the new tiny leaf that was growing... Some days later and now the orchid is starting to have a yellowing leaf and I am worried this could now kill my orchid. So I was looking for some advice on how to proceed.

The orchid is potted in a sphagnum, bark and perlite mix, the roots look green and healthy and I fertilize with about 70-100 ppm of N on each watering. I also just applied some Kelpak for some more root growth.

Thanks a lot for reading all this, below I attach a pic of the said orchid

[estación seca]

I can't remember your growing conditions. Temperatures day/night? Humidity? How do you decide when to water?

[Alvaro78]

My temperature stays mostly consistent at 22-27 during the day and drops to about 20 at night. My humidity usually stays between 45-60% and I water when I see the roots start to silver and the media starts to feel really dry (easy to notice because of the sphagnum).

[estación seca]

I can't look up its ancestry on Orchid Roots right now. It's been down for a few days. But photos show it probably has a lot of ancestors - like Phal. gigantea - that want high humidity and high temperatures, all the time. Such plants carry fewer leaves in cool homes than in ideal conditions.

I would suggest finding a way to raise the relative humidity to 60% and higher, and give more heat.

It's a good idea to look up the ancestry of plants before buying. This kind of Phal. is not easy to grow well in most homes.

[Alvaro78]

I see, yeah it has phal. gigantea as the pollen parent. I tried with this one to add more sphagnum moss so that it can have a bit more of humidity.

Is there anything I could do right now to help it apart from the increased humidity? It just seems so weird to me that it suddenly started to yellow 2 days after I snapped the new little leaf because it had been doing just fine for like 3 weeks. Could it somehow have some rot in the stem and that caused the new leaf to snap so easily? Although I remember that when I snapped it it was all green and fresh but everything came off and no leftovers were left on the plant so that kinda surprised me.

[rbarata]

What is the composition of the medium?

[Alvaro78]

It's equal parts of bark and Sphagnum moss and then like 15-20% perlite

[rbarata]

My intuition tells me that you should take the sphagnum out.

[Alvaro78]

I see, I checked the roots and they all look really green and healthy there is 0 rotting so you think they could soon start to rot because of the media? I always let it dry out between waterings but I know that in the Spanish summers I'll have to water every 2 days so I wanted to prevent it a bit since I won't always have time

[rbarata]

Perlite and sphagnum are water retentive. With that propotion (50 %) it might be suffocating the roots (they need humid air around them).
I would keep the perlite and reduce the sphagnum to 20%. I would also increase the bark size as it seems to be too small.
I don't know where you live in Spain but my summers have hot temps and day humidity often as low as 15%. I use only coarse bark or a mix of bark+LECA +Perlite or coco chips and the plants can handle it very well. The "secret" in this environment is to increase watering.