Help with I.D....duster, filter feeder or what????

[EuroGTI]

So I woke to hundreds of these In my tank today. At first I didn't sweat it much, but then started noticing how bad they have exploded in population. What are they??
What really has me wiereded out is they swim. They pump around almost like a jelly fish! I cleaned my glass and then noticed them moving around. Any help appreciated. First time I run into these things.
http://i158.photobucket.com/albums/t83/fast4imports/E66D6C8F-A690-42F8-97F6-9F48196A080A_zpshfqsr2zl.jpg

[criticalencore]

Colonial hydroids maybe? Nuisance if so

[cloak]

Hydroid jelly fish.

http://www.wetwebmedia.com/jellyidfaqs.htm

[EuroGTI]

I saw that link also in my research today. Thank you! If I read correct these are non nuisance, and should taper off naturally? I have read mixed reviews? With the hundreds that exploded in my tank I hope they are not bad. Any I'll affects on fish?

[cloak]

No worries. They're quite common, and the population should subside given time.

[EuroGTI]

Awesome thanks. After much research I'm surprised how common they are. Never had them in any of my tanks!