Coco Worm

I have had a coco waorm now for months and it just lost one of its crowns. I have been using kalk in my top off water. 1/4 teaspoon kalk to 1/4 gallon water morning and night. Anyone think this could have stressed him out?
Adam

2 Oscellaris Clowns, Orangeback Fairy Wrasse, Green Mandarin, Red Lobophylia, Yellow Fiji Leather,Branching Hammer, Plate Coral, Long Tentacle Plate, Red and Blue Mushrooms, Ricordia & Yuma Mushrooms, Coco Worm, Devils Hand Leather, Toadstool, Purple Mintipora, Sun Coral, Orange Gorgonian, Red Gorgonian, LPS Maze Coral, SPS Scroll Coral, SPS Birds Nest, Orange Plate, Maxima Clam, Green Finger leather, Serpent Star, Long Spinned Urchin, Green Emerald, Various Snails and Hermit Crabs

 

They don't like high Nitrates. What is your Nitrate level?

Also, have you seen any crabs or fish pick at the crown?

 

About 7ppm nitrates. I moved him recently though.
Adam

 

my cocoa worm sheds his every now and then... should grow back

 

I hope he does regrow. From looking great to the 2 heads acting wierd, then losing one head and now both head I think are gone.
Adam

 

I saw 2 hermits craw around the opening. Should I take him out of the tank or leave him alone?
Adam

 

i wouldnt worry, mine just lost both heads and now they are back... give it about 3 days and you should see some growth