Random Thoughts

I have this bubble algae growing in a few places in my tank and in some places it is very heavy. I am not worried about it and kind of like it, but anyway, I noticed that it is just growing on my home made cement rock or the cement on bottles and none of it is growing on any real rock.
It started in my algae trough which is a screen coated in cement. The trough was so filled with this bubble algae that it overflowed and the entire thing fell into the tank from the weight.
I find this ...