7 month old tank questions

[clarkiiboi]

To start off I have a 75 gall. with about 75-85 lbs LR and all LS, about 3 1/2 inches (will increase soon). I have an orange chromis, 4 blue devil damsels (taking back as soon as I can catch them), a coral beauty that is in a hospital tank (cloudy eye and doing better, treated with hypo.) an arrow crab, scotter blenny, a few turbo snails (working on better cleanup crew), and 3 anenomes. Para. are amn 0, trites 0, and trates about 10, and salinity 1.023-25
Questions are: 1) I now, for the first time, I see bubbles in my LS. There could be more but I only see it in the LS at the front of the tank, next to the glass. Is this bad? What is it? Isnt this something that happens in a "newer" tank?
2) I went searching with the flashlight after lights were off and see these brown worms in the LR---they seem to "stretch" about 1 to 1 1/2 inches, but when the light hits them, they retract. Definately not bristle worms. Its just a plain worm, not centopede looking, they are smooth (meaning no "legs") Did a search and so far I havent found them. Any ideas, I dont think they are bad, just curious as to what it is.
Thanks sorry so long

 

[striker]

The bubbles are a positive sign of your sand bad at work. I believe it has to do with gas exchange and nitrate conversion(not sure). The tiny worms are filter feeders and another good sign of healthy live rock. I'm not sure of the exact name but I have tons of them (different types). I also have the bubbles and many colors of algae in my sand.

 

[bang guy]

The bubbles are probably Nitrogen gas... this is a good thing, what a DSB is for.
The Worm sounds like a Cirratulid or a Teribellum, both excellent detrivores and crucial to a healthy sand bed. I'm surprised your Arrow crab hasn't found it/them yet. I guess you keep it well fed

 

[clarkiiboi]

Thanks you two! Now I know the sand bed is ok. (I couldn't remember what I read here before about that same topic)
One last question: Striker read my worm issue as in the LR and that was correct.
And Bang Guy I'm not sure if you thought these worms were in the LS instead of the LR. You said these were crucial to the LS, but what about the LR--is that still ok, or does that change what species of worm you think it may be? Just trying to be careful thats all.
And my arrow crab is more concerned with "looking pretty", I think he/she is vain LOL Thanks again