Black Slow Moving Small Dots In Tank....

HI --

I wonder if any of you could help me identify these --- black/brown dots --- these appeared 1 wk after I introduced some Anacharis to my tank.... they are everywhere.

About 0.5 mm ( very small) . They are on the tank walls,, ,, they seems to be eating the algae or biofilm on the tank wall ( leaving a clear trail) , and they are all over my java moss ( but doesn't seem to be eating them) but they seems to be nibbling on the Anacharis... and attached to my dead parts of the salvinia.

I think they move very slowly.. and now at week 2, they have not grown in size...

These are some photos I capture with my microscope ( 10 x objective magnification).. they do have spikes on the margin..). Thank you in advance. ( My initial thought is -- they are snail larvae... but now I don't think so..... ) THANK YOU!!

 

I am interested to see what these are too!

 

freshwater limpets??? they aren't quite as round though... hmm. do you think they might just be pond or bladder snails? the spikes do confuse me.

 

hi. I need to get a biology text book! haha. I wondered about limpets. I put some assassin snails in there . but either because the "UO"( unidentified organisms) are too small or they are not snails ,, the assassins just.. by pass them without a second look... still searching for identity.. wonder if they should be left alone or destroyed!! I have thought they moight be ostracods ( seed shrimps) but.. they are not really that motile..

 

They are most likely one of the many species of ostracods - seed shrimp

 

They are most likely one of the many species of ostracods - seed shrimp

OH thank you.. yeah .. was reading about ostracods --- but do some ostracods just move slowly--- these barely moves..... and they do not look motile in in the water column.. just on surfaces. Are they harmful --- do I need to get rid of them? Thank you!

 

If there are large patches of algae they will pretty much camp out on it until it is gone. One of my friends says their swimming reminds him of "drunken bumblebees".

There is a lot of variation in appearance, but all seed shrimp have clam-like shells. They have to open their shells to swim or feed - occaisionally you may see the end of legs or antennae sticking out while feeding or swimming.

Most seed shrimp are harmless detritivores

 

There is a lot of variation in appearance, but all seed shrimp have clam-like shells. They have to open their shells to swim or feed - occaisionally you may see the end of legs or antennae sticking out while feeding or swimming.

HI Thank you-- I have never seen them swim. but they are.. so .. smalll. I hope they don't nibble on my plants that's all. ! thanks once again.