Help!! coral emergency

[mcginnisandrew]

Long story short, about 2 weeks ago my duncan coral colony died, over several days. This was a colony of 7 polyps, which had recently divided from one polyp so they were all clumped together. I THINK it starved, although im not sure because it had plenty of light, but i don't think i was feeding it with mysis enough.
my PH at the time of the coral's death was 8.0-8.1, so i added a buffer, and my PH since then has been 8.2 consistently. All other tank parameters have remained mostly consistent since then. my calcium and strontium were on the low end of the safe side, which i adjusted.
Now, my dendro is starting to die. I think it may be starving, but i have been feeding it (small amounts) of mysis almost every day. So currently i have a bunch of mysis sitting right on top of the dendro (its only one polyp) with the powerheads turned off.
What do you think might be wrong? if anything?
I also have some little snail things that popped up recently. maybe chitons or something? I brought some in to my LFS and they said they were not dangerous, although i want to make sure. Also, these little tiny spiral like things recently popped up and they are a bunch of them all over the glass of my aquarium. ID please?
Also, there are all these little tube like things that send out a thin, spider web like line into the water whenever there is food in the tank. if a piece of food hits one of these spider web lines, it will start to like "reel it in" to its tube and then eat it. These have been around for awhile and i don't think these could have killed my duncan and made my dendro sick, although i have seen them attach to the skeletons of other corals.
heres some pics

[mcginnisandrew]

[DaveAngie79]

not sure what killed your coral, but i did see bubble algae in one photo take care of that with some emeralds dont pop them it will become worse, the snails are fine they wont hurt anything i have had them for years they help keep everything clean they dont live long, it looks like the others are some sort of feather dusters also a good thing helping filter the water , i hope this somewhat helps hope u figure out what killed your duncan

[the droob]

I have a large tube worm that sends out a spider web like net and it often covers my zooanthids but they are doing fine when the worm pulls in the net to feed the zoo's open up again,this has been hapening for about two months,thats about all I can help you with,good luck

[mcginnisandrew]

hmm i don't think the spiral things are feather dusters, they are really really tiny, but i guess they could be.
The tube things are also quite small, about 1/4" to 1/2" long

[carpas]

Do you track your alkalinity? The buffer could be causing alkalinity swings that are hard on inhabitants.
My guess for the critters in question are limpets and are a fine addition.
The tube things may be vermitids or other sessile snails. They can be annoying but probably aren't hurting anything unless you have plague proportions. Their numbers wax and wane based on available food.

[SleepyJ]

Pic. 1 has bubble algae and a bunch of vermetid snails. The vermetid snails are the ones shooting out "webs." Vermetids are mostly harmless but do irritate corals. Picture 2 looks like a limpet. Limpets are for the most part reef safe, but at times they can munch on corals, so keep an eye on them. Picture 3 is spiorbid worms which are reef safe and will disappear once your tank matures. Hard to tell what pic. 4 is: could be the underside of the limpets or if that is top-side then they could be flatworms.

I'm not sure what killed your LPS. Have you checked your nitrates and phosphates?

[mcginnisandrew]

thanks guys.
Im guessing it was just bad water parameters at the time.
The dendro is recovering, because of the massive amounts of food im now giving it.
I'm going to do an iodine dip for all my corals just to be safe, and i'll watch my parameters more closely.

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