Your problem is most of the growers on this site live in the USA and I'm here...

Anyway, a good clue is what are they potted in at the moment? Big lumps of bark? Pebbles etc?

For what it is worth mine are potted in medium sized treated pine bark + perlite.

The ancestors of the modern hybrids grew in nature on rocks or trees so the roots are exposed to air and it doesn't matter if some roots are growing out of the base of the pot or in the air.

Perhaps the RHS has some good notes?

Found a link for North England

Phalaenopsis culture notes

I've taken pine tree bark and chopped it up into pieces and had great success with that. It starts to decompose after a few years tho. I've also purchased an orchid mix commercially like this from a local orchid store:

http://www.ebay.com/itm/like/380180425700?lpid=82&chn=ps&ul_noapp=true

Hi guys, thank you for the advice and the links!

They are currently just potted in large lumps of bark - though my mum got them from a bargain store that doesn't usually sell plants, so I'm not convinced of the quality of the bark, it looks like it's beginning to break down to me..

I've never dealt with orchids, so I wanted some advice instead of just going out and buying the first random orchid compost I saw.

From what you guys have said/ what I've read I think I'll go for pine bark with some perlite. Though I'm unsure whether to add spagnum moss as well?

Generally information says to add it if you live in a quick drying environment? I would assume I wouldn't need this in the UK then?

Thanks

In that case what i'm going to do is order some bark from an orchid supplier in the UK that way I know it will be suitable and treated.

In terms of spagnum moss - does it make a difference where it's from? I've seen claims new zeland is better or Peruvian etc. But it's very expensive compared to what I can just buy from Amazon?

Also - I think at least two of the three orchids need larger pots, but from what i've read orchids don't like a too much room? I've attached pics - an opinion on if they need a larger pot would be great :)

I think they look fine. When the roots stick out or hang out of the pot...then they need bigger pots. Those phals look pretty happy to me.