Big bug in my DWC reservoir?! WTF

WTF is this thing and how is it living in my reservoir?!

kill,l thata wierd mother fucker its makeing me freak just looking at him HE MUST DIE!!

Is it a damsel bug? Pics blurry and can't see true color markings. I am guessing its squished tho.

Could be dragonfly nymph. Where do you live?

it's like black with a blackish gold tint to it's back. there is one white marking on each leg and each antenna. It's not a damsel bug or a dragonfly nymph. I'm guessing it's just some weird bug that crawled in through the hydroton. But who knows it could be living in the water. idk?! and North eastern USA