I haven't done this lately but I used to buy coco fiber from the pet store like Petco, Petsmart, etc. They sell it in a brick for reptiles. I would just soak the brick in a 5 gal bucket of warm water overnight and by the next morning the coco fiber had soaked up all that water and was ready for use. If I remember right it was only about $5 for a brick. I used mine as seed starter and one brick made enough for several trays of seeds. It's kinda of a weird trick but it worked for me.

Houston garden centers usually carries it, there is one on Nasa rd 1 and another along I-45 in League City.
Tally HO!

the one at Nasa rd 1 and 45 moved to near Baybrook Mall.