I tied HC onto the wood with black polyester thread.
Yes, I've thought about fish...and shrimp.

In the past, I've added fuana and flora together and it caused me grief. My new policy is not to add any fish until the scape is complete. That way I can keep things under control, rearrange, do fast water changes with cold water, blast Co2 if need be, etc without worrying about killing anything.
Also, I don't know what type of fish will fit the tank until it's finished, and I currently have no idea what it's supposed to look like when it's finished