I bought some coco garden mulch from Costco online and I was surprised to see it was almost identical to some I had bought to repot orchids at a significantly higher price. https://www.costco.com/megamul...

This stuff has turned out to be too expensive to spread around the garden but it is a bargain for an orchid mix.

Well the price of goods has always fluctuated. I used to think that it was based on supply and demand.
But as I have "gained life experience", it seems to be more and more based on what the seller thinks that their offering might be worth.

Glenn, that silly friend of mine, opened my eyes to e-bay and orchids. There are prices there that will blow your mind. One of the most common things done is to offer a tiny seedling at outrageous prices claiming it is Rare!! A plant realistically worth $5 is offered at $40 because it's rare.
OR
The crazy idiot offering a rare "Orchid Species" for $45! They list it as Paphiopedilum niveum X Paphiopedilum delenatii. That is a hybrid you "dope"! But maybe that's why it is a rare species?

Nothing surprises me anymore in pricing Alice, nothing. But I am glad that you found it cheaper.

Oh I forgot.
Oh Alice, that material out of the bag looks very nice. I wish you much success using it as your media. I personally have never tried it. I was pretty much always a 'bark man'.

I am curious how it works out too! I noticed that our local Costco here in East Lansing had the compressed blocks this spring.

I have one brick left and I just found a bag of that which I had bought from an orchid supply place. I will try and remember to take a pic comparing them. I am using it for garden mulch but I will certainly save a bit for orchids.

I got coco husk chips, I think from Kelley's Korner, and have two mini phals and two regular phals in them, they seem very happy.

Sally, you are the first person that I have ever met who grows in that media.

I don't know what that means except to say whatever works for every person is what they need to stick with.

Instead of Sphagnum I use coconut fiber every so often on some Orchids. After loosening them a bit.

I got that compressed coco brick from Costco too last summer..tested it. Well, it is not for my orchids..but I am still experimenting. Have put some in old nylon stockings and used that to somewhat cushion Phal roots.
I tried to use them as is, after of course bloating them with some water..my thirsty Oncidiums not happy...I guess I should add some more clay rocks or more pumice into their mix.
But I did use some and added it to my Hoya shooting star which has always been a thirstier hoya..and it has adapted well. Ah yes, learning from my Oncidium mistake I added some pumice..so Hoya is okay.

I would say for orchids we need the other part of the coconut..in the Philippines we just use dried out coco husk ..there has to be the fibers in there still present..that truly works well for any orchid. Especially there where it rains so often and orchids there are planted outdoors in partially shaded areas, temps never going down 70F.
Over here in the US the fluctuating temps will be an issue as you use coco parts, unless one has good growing environment control and ventilation.

I think the compressed coco brick is good as add on to soil but not used alone.Got to add pumice or other chunky aggregate. Coco husk fibers..that will be the one much better for orchids.

I have used coir brick but not for Phals. That was very fibrous. The coconut chips have some fibers in with the chunks, mostly chunks.

The coir chips I bought from Costco were almost identical, except for the size, to those I bought from Green Barn. The chips from GB were about 1/2 the size of the ones from Costco but in all fairness the Costco ones were supposed to be mulch.

As Tarev noted above, hoyas seem to do well in the compressed coco brick material when it is amended with perlite or charcoal. I had a hard time keeping the right moisture content when I used it straight --about 30% perlite mixed in made all the difference under my watering schedule.