To feed or not to feed? 3.5 inch crocea


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My crocea has had its exhalant siphon fully opened for two days(mantle to mantle). Is this stress, hunger, or both? It is now about 18" from the halide in direct light and low flow. I bought some homebrew phyto and some Kent Micro Vert today from the LFS. Will supplemental feeding help, and do any of you think this is a hunger issue?

Also, how does the clam dispel unwanted particles from its innards? I have seen a couple of bits of detritus fall in to the exhalant area. Is this to be concerned about?

Thanks for your resources,
Clam gaping

Clam gaping

I have seen my clams shudder and close quickly expelling whatever it had in its gill area in so far as detritus or larger pcs of food that were not eaten by the fish. Phyto feeding should not be necessary but in my experience does not hurt, I dose weekly for my acro's.

What are your water parameters? Has your ph and temp been stable? What intensity is your lighting? There are many factors that could cause clams to gape and the amount of gape on yours does not sound good.

Let us know how everything is
I have 2 175 MH. I thought it was odd that when I turned off the halide above the clam(acclimating a new coral) the siphon shrunk to a more normal size. The temp runs 77-79, and the pH stays at 8.2. The nitrates are 0 and dkH is about 5. Calcium runs around 500, which I know is a little high. Other than that I do not know what it could be.

Your alkalinity and calcium levels are not balanced. Because your calcium is so high, the see-saw effect has lowered your alk to 5 dkh. Natural seawater has an alkalinity of 8 dkh (aquariums are usually maintained at an even higher level. Perhaps that's causing your clam to behaved in a stressed manner. Do several, small water changes until your levels are closer to natural seawater's. Or, add more buffer to bring up the alkalinity and lower the calcium.
Last night the clam hopped off its rock and has settled in the sand next to it. It is upright, and seems to have the byssal gland in tact. It did not leave any residue behind on the rock. I had moved it last night to try and position the siphon a little higher so maybe it would be less stressed. I guess it knew how to do the job better than I could. I am going to leave it there through today and see how it does.

Potsy, I loved watching you on Happy Days!
Anyway, I will test today, because those results are not up to the minute. Also I have about 10 gallons of water that has been mixed and curing for about a week. Would a water change help or hurt? What buffer do you reccomend?

I am giving Lugol's solution and strontium as reccomended, as well as a small dose of coral vite each week.

I want to help the clam be healthy, and fix any small problems before they become large ones. I know clams can go fast, so I will do what I can.

Thanks for your time,
Bad news.
It did leave some byssal tissue behind, about a 1/2" lnd by 1/4" wide piece attached to several threads. The rest of the gland is in tact though. I just did not notice the tissue before because it was laid over into the rock. I placed the clam in a seashell half with some live sand to keep it upright and put it back down in the place where it had moved itself to.

Somebody please respond. I am leaving for vacation today, and I do not want to come home to a fouled up tank and an empty clam shell. I have really gotten attached, if that is possible.

Westpat said:
Bad news.
It did leave some byssal tissue behind, about a 1/2" lnd by 1/4" wide piece attached to several threads. The rest of the gland is in tact though.
I just lost one of my clams this week by the method you explained. It hopped off the rock one night and left it's byssal thread behind on the rock. Two days later it was dead. Before that, the clam gapped most of the time since getting off the rock. :(
I retested today and my Ca is between 460 and 480, and my dKh is 7.0. I turned off the mag drive and fed the tank some phyto.
I put it above the clam, above my oyster(don't ask), and above the feather duster. It floated down and I could tell that the clam was uptaking it. Other than the inhalant siphon open wide it seems to be normal. Maybe I am overreacting. I am going to adjust the rockwork so that I can move the clam a little farther from the tube anemone.

I guess it is in God's hands now.

Thanks for the input,
I am beginning to strongly suspect the tube anemone of stinging an making the clam run, but I just do not know how it could have done it. Anyway thanks to my wife's inventiveness there is a tupperware lid barrier between the two. We are going out of town til Friday so we will see what happens.