Larvae in water trays - ID please

[nimbulan]

I had some of these last year and dumped the tray out to get rid of them. This year I thought I'd try to figure out what they are. They definitely don't look like mosquito larvae and seem too thin and long to be fungus gnats. They just appeared suddenly over the past week and wiggle around on the bottom of the trays. It's hard to get a measurement when they move so much but I would estimate they range from 3-8mm long. Any ideas?

 

[Cthulhu138]

Look like some kind of midge larvae.

 

[SFLguy]

Sometimes they'll be red too, they're also called blood worms aka baby midges

 

[nimbulan]

Are they anything to be concerned about or should I just leave them alone?

 

[Tanukimo]

I don't think there is anything to worry about. I have them in my Utricularia tub outside.

 

[Cthulhu138]

The majority of species just feed on algae and detritus although, there are a few that will bore into plants.

 

[nimbulan]

Thanks for the tip, I found a very similar picture on Wikipedia here: "chironomids or nonbiting midges"