Help! Wierd tiny creatures in my tank

[Tetra22]

I have a 10 gallon fw tank with a 3in. long lobster/crawfish in it, I just looked inside and saw a ton of little brownish spots on the glass. I stared at them for a second and realized they were moving around! They're only maybe a millimeter long, I thought about maybe a snail problem, but they seem way too small and move too fast to be snails. Plus I don't see how a snail could have gotten in there. So does anyone have any clue what these things are?!?!

[Etunes]

probably snails, they come in on plants and they make babies, FAST.

[Tetra22]

But I dont have any live plants in there. And I havn't even done anything with this tank in like a month. So nothing new has changed and they just showed up.

[WhiteDevil]

moving as in swaying or moving as in actually moving positions completely?

How long has it been set up, sounds like diatoms.

[Tetra22]

Moving as in completely moving to diferent areas. Changing directions too. This tank has been set up for at least 6 months. but It has been a while since the last water change.

[WhiteDevil]

little brown dots? can you see any cell structure when you look at them close or with a magnifying glass, even a 3x will show this cell structure, if it is I think they are some form of POD due to maybe overfeeding. From what ive read on them because I had something like that, and everything I found out points to edible and 100% OK for the fish, dont feed for a few days or feed very light and do a wicked gravel vac but stir the gravel to get em up into the water then suck em down.

[Tetra22]

Ok thanks, I'll go do that.

[WhiteDevil]

Do you have a hang on back filter? if you do, vacuum the snot out of that gravel. there is no to little waterflow in that gravel so bacteria growth is at a minimum.

[Tetra22]

Yes I do and ok I will. Thanks for the help.