What's eating my pods?

[ryan115]

I was at the lfs the other day and noticed that the pods in their fuge are huge compared to mine. Theirs are about 2.5-3.5mm long while mine might not even be a mm. I have lots of them they are just small, so i was wondering if anything that is in my tank might be eating them. I dont have any fish in at the moment because of katrina. The only things that i could think of would be bristle worms or some little flatworm things that are crawling on my glass all the time. The flatworms sound just like the ones that reefnut describes in the hitchhiker thread but they are sort of a translucent white. Could either of these be the culprit? :notsure:

 

[rcp_pd]

yup. i would say so. how old is your tank?

 

[ryan115]

about 3 years old... i just put in a fuge last spring. Also which one would it be and how do i get rid of them? ALso these bristle worms come out to eat when i drop some shrimp pellets in for the crabs. They come out in droves and fight with the crabs for the pellets :scared:

 

[rcp_pd]

From what I have read and seen, bristle worms wont really affect your pod population (someone please correct me if I am wrong). It is the flatworms that will be having a nice snack on them. I dont think that the flatworms would damage your pod population to the extent that you will only have a few in your tank but I would rather have them out than in there. I hear that there is a flat worm exit you can buy to get rid of them...not too sure where though.
I have also set up a sump/fuge combo in the beginnig of the year on my tank and although I see thousands in the fuge and bunches on the glass in the DT, I do not really see the big ones as much. I originally bought about 30 or so of the big ones seed my fuge with but I dont see them as much as I do the smaller ones. :notsure: who knows where they went to? I can only guess that the LFS that you went to has had their fuge set up for a loong time now with no predators and that is why they have grown.

 

[reefnut]

The bristle worms are good scavengers so don't worry about them. There is a flatworm that will feed on copepod but they tend not to become immense in population so most of the time they have little effect on the overall pod population.
Now, there are two types of "pods" we typically see in our tank... one bring copepods which are very small, even at full grown. Amphipods are larger and easier seen.
With your tank not having fish I would assume the food supply is limited. Feeding small amounts of DTs or other fine filter foods will help... even putting small amounts of fish food would help. Typically, all scavenger's populations are determined by the food supply.
The first picture is a copepod, the second is a amphipod.

 

[smarls]

There are differnt types of pods that come in different sizes.
The ones I believe you have from your description are copepods. The larger ones that you describe as being at the LFS sound like amphipods.
It may just be as simple as your tank not having amphipods, but having copepods. That said, flatworms are not a good thinhg, and it may be worth taking some time to eliminate them.
As for the bristles and the crabs fighting for food...these things happen! Bristle worms are great detrivores, and I really believe you want them in your tank. If the worms and crabs tussle a little, so be it. If you are concerned, you can add some extra pellets to make sure everyone is fed, but personally, I would let them tussle for the food and search for other things to eat...they are made to scavenge.
HTH
Stewart

 

[ryan115]

thanks!!! also i wasnt saying that it was a bad thing, them fighting for the food. I just think its hilarious that a bristleworm can pull the pellet away from the crab.

WHen my friends come over i feed the bristle worms just to watch them come flying out of the rocks :joy: