Are my orchids okay? + Fertilizer questions

[Ruby_House]

Hi!

I was wondering if my orchids looked alright, I have had 4 of them for almost a year ( Epidendrum, Zygopetalum, Oncidium 1 and Dendrobium phalaenopsis) and recently got a Dendrobium nobile and Oncidium 2 from work. I'm a bit worried for Oncidium 1 due to its colour and spots on the end of its leaves. After looking around it could just be due to cold temperatures but I'm not sure. My poor Zygo got pushed by my cat a couple times so some of its leaves are bent but it seems to be growing more bulbs. My Dendrobium nobile had keikis growing on it when I bought it and I've read that I should wait until the roots are longer before separating it. but I was wondering if it had too many of them (4)? I also noticed that the tip of its leaf is a dark brown maybe an infection?

Finally, I've been meaning to start fertilizing my orchids but I'm having trouble choosing the right one. The ones I've seen near me are Plant Prod 25-10-10, Schultz 15-5-5, Algoflash 4-6-6. Which one would you guys recommend?