Thanks Sunil!

Under water I have 2 rock piles, a large ring of 1' tall concrete pilings, and a fake PVC tree type structure. I also plan on adding a bundle of cedar limbs in a shallow corner, with a few larger brush/log pieces around it.

I do think you're right though, I have enough concrete to make 5 more of those tentacle type items and it would probably do some good putting them all together there. Thanks for the suggestion!