can anyone ID these?

[myDigitaLife]

about the size of a grain of sand...

http://i170.photobucket.com/albums/u262/mydigitalife/whatisit-03.jpg
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about 1/3" tall, hanging upside down on a tonga brach

http://i170.photobucket.com/albums/u262/mydigitalife/whatisit-01.jpg
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I truly appreciate any info you can provide, thanks!

[jdieck]

A Copeopods
B Flatworm
C Sponge

[philbo32]

A) isopod (but need a clearer picture of its eyes and smaller limbs to be completely sure)
B) flatworm
C) common sea squirt, because its barrel shaped and you can see cilia (which can be comon in some spp. of sea squirt) that cause tiny currents at the top of its large opening for filter feeding.

Sea squirt;

http://home.uchicago.edu/~egrey/sea%20squirt%20diagram.gif

Isopod mostly feed on detritus, and in my opinion are good for the ecosystem of any aquarium, whilst at uni I did a lot of research on the freshwater isopod asellus aquaticus and the breakdown of leaf and organic material in lake systems.

Asellus Aquaticus;

http://www.kuleuven-kortrijk.be/facult/wet/biologie/pb/kulakbiocampus/insecten-ongewervelden/vijverfauna/asellidae/t-Asellus%20aquaticus%201.jpg

http://www.iii.to.cnr.it/limnol/bentos/foto/Asellus_aquaticus.jpg


More recently I have been researching bioluinescence in asellus and mate attraction versus predator trade offs.

[myDigitaLife]

Thanks for the info. It's good to know what these hitchhikers are.

[LeslieH]

A - Munnid isopods: scavengers, micrograzers, herbivores
B - acoel flatworm, looks like an Amphiscolops species - micro grazer
C - Scypha sponge, commonly known as pineapple sponges

[philbo32]

I am mistaken, C is a Scypha sponge. Doh...

[myDigitaLife]

Thanks Leslie! I googled "Scypha sponge" and I think your id is dead on.
I found yet another critter in my tank that I had never noticed before, its 2/3" long and is attached/emerging from a rock.
I tried to find it online but couldn't locate any info on it...any clue what it is?
http://i170.photobucket.com/albums/u262/mydigitalife/greenworm.jpg

[LeslieH]

There's not enough detail but overall it looks like the green algae Neomeris.