My Crocea Clam suddenly died - any idea why?

[debby]

Folks, I'm looking for some insight please.

220 gallon, mostly softie tank.

specific g 1.025/6
temp 79-81
ph 8.2
alk bet 8.4 and 8 over 4 months
calcium 450
phosp .06
mag 1300

Nitrates - between 10-20 - cannot seem to get them down.

fish - two tangs, (desjardins, hippo), a few small wrasses, pj cardinals, 4-5 sm damsels....2 clowns
zillions (clean up crew) snails, hermits
2 cleaner shrimp

corals - assorted paly, zoa, a few shrooms

3 small (3-7 polyp) acans
1 spectacular duncan (about 10 heads)
beautiful cloves of various color and size
2 small Cabbage leathers
1 Leather toad-stool

all of these are doing nicely

running skimmer, CS2
UV sterliizer
GFO & Carbon (separately)
using RODI water
still have high nitrates -

SO....I put in a biopellet reactor.....

over several (at least 6 weeks) with a very small amount of pellets - no change in nitrates.

a week before leaving for work/vacation, i added 100ml Dr Tims waste away. had a bit of cloudy - turned skimmer back on and did small 30/40 gallon h20 change.


came home to a dead CROCEA clam and a missing paly (who was having a 'baby', a GIGANTIS?) had DISAPPEARED - no trace but the frag/mount -

Everything else was fine! thriving in fact. I'm beginning to think that the bio-pellets and dr tim thing lowered the 02 levels and killed the clam, but it's just a guess after testing everything else i could.

any ideas??

ps. it was a beautiful clam, video of when he was happy. I am pretty heartbroken about it dying.

 

[Sniperhank]

Besides the paly, I'd say the clam was taken out by pyramid snails. Clams are funny, they look like they are doing fine even if they are slowly wasting away.

 

[Gregcoyote]

I had something similar happen. I started working my Phosphate level down to .05-.07 for my SPS corals and when I got there both my clams died. Everything else looked great.

I have seen some healthy clams in some pretty dubious aquariums doing fine.

 

[Sniperhank]

That's interesting.