Worm in a sand tube – 06/14/07
Hello Crew,
<Hi Carlos, Mich here.>
After 10 years w/o a marine tank I decided to dive back into the hobby.
<Come on in the water's great!>
I just setup a 70 gal tank. I have one lone damsel and about 30 lb of live rock (on my way to get more.
<Hopefully this new rock is fully cured.>
A few days after putting the rock in I noticed what appeared to be a thin walled tube made up of sand coming from one of the rocks. The tube is made up of some sort of slime and is clear except for a thin layer (1 grain thick?) of sand. Yesterday I turned on the lights and caught what appears to be a very small (barely visible) black worm scampering back to the rock inside the tube. I've seen it twice now. It seems to come out at night then back to the rock when the lights go on. Can you identify?
<Sounds like a type of feather duster worm, likely a member of the family Sabellaridae.>
Is it bad for the tank?
<Nope. More here: http://www.wetwebmedia.com/feather.htm >
Thanks in advance for your help.
<Welcome! Mich>
Carlos

Confusing worms? Reading, on... WWM – 03/18/07
Hey guys,
<Josh>
A while back I wrote you about a small oyster toadfish that I rescued from a friend. Your advice was much appreciated, and now he is happily living in a 40 gallon tank (at least until I can afford a bigger one ;). He is actually making his fog horn like mating call all the time!
<Neat!>
(My friend had never heard it before and was jealous). Anyway, I am doing an internship with a local aquarium
<Ahh, very good>
and they donated some small brittle stars to my tank to help stir the substrate.
<Nice>
I apparently also got some worms with it and I really don't know what they are.. maybe some kind of fireworm??
<Polychaetes of many types are very common. See WWM re>
They are about an inch in length and orange-red. They appear not to have any bristles and bury in the substrate. When they do, they send out 3-4 long hair like red tentacles that just sort of sit on the substrate and move with the water flow. They don't appear to move much around the tank, if at all. I have two turbo snails and the toadfish and would like to eventually make it more of a reef tank. Are these worms harmless?
<Most are>
Should I get rid of them now before they multiply or just leave them?
<The latter for now>
Which brings me to my second problem. I can't get the nitrate levels down. I have done many water changes up to 70% and it brings the levels down slightly, but within a few days they are back at the highest level
<Yes... Batrachoidids are big feeders, waste makers...>
I can read with my "Red Sea Marine Lab" test kit. I don't have a protein skimmer, just a standard marine filter which pulls the water over a sponge like filter, through a bag of carbon and then over some rocks the bacteria are growing on. A friend suggested getting rid of the filter, but I clean it every other day so I don't THINK that's causing the problem.. so the only thing I could think of was maybe there is stuff decaying in the substrate, hence the desire for worms and brittle stars. Think that might be the problem?
<See WWM re Nitrates... the search tool, indices...>
This tank is about 2 months old without any hermit crabs, but the nitrifying bacteria should have become more than established by now right?
<You need their complement of denitrifying bacteria... a place for these to be...>
oh yeah, and I am very careful about how much I feed my fish so there is not excess food in the water.
Thanks for your help!!
Josh
<Be reading. Bob Fenner>