• Looking to buy a cephalopod? Check out Tomh's Cephs Forum, and this post in particular shares important info about our policies as it relates to responsible ceph-keeping.

Do you use a Marine Hard Coral Additive? (i.e. calcium, kalkwasser,etc.)

Jan 4, 2006
I have been researching all the cuttle articles I can find (TONMO, the ceph page, goggle) and can't find anyone recommending calcium.

I was thinking how does the cuttlebone grow without calcium added? I understand why octos wouldn't need it, but that cuttlebone has to grow awfully large-awfully fast. Could that be a limiting factor in the raising and breeding of cuttlefish?

I noticed in some of Colin's photos he had corals, did they receive additives? I also noticed that the brand name "Fuji Mud" is talking about the calcium and minerals in mud patched just outside the reef systems.
Search results for: '' - Bulk Reef Supply
Search results for: '' - Bulk Reef Supply
This is also where cephs like cuttles and muck animals mostly live. Could they need these conditions to thrive?

Unless anyone can give me a reason not to do this, I am going to try supplementing my tank as if I was stocked with stony coral. I will be learning how to track absorption of calcium, so I can see if it is actually being used.
I think it's supposed to be small enough that the water test kits cannot detect even a trace of it. Not sure about the exact amount though...

Speaking of Calcium, I've also seen a friend of mine use it as a PH buffer or something...not sure is it good for the coral and fishies though (not cephs, he says he'd rather eat them than keep them.)

Shop Amazon

Shop Amazon
Shop Amazon; support TONMO!
Shop Amazon
We are a participant in the Amazon Services LLC Associates Program, an affiliate program designed to provide a means for us to earn fees by linking to Amazon and affiliated sites.