Hey guys, just want to chime in.

That 'sponge growth' is actually a piece of sponge.

My phals also came with pieces of sponge packed in the potting mix. Retains water, doesn't rot.

It's sponge.

:waving

Lol. Omg! Really? I didn't notice it in the mix at all and when I finally did they're all stuck to the roots making me worried. -.-"