Shrimp & Calcium/Minerals Requirements

[Kalita]

I'm new to keeping shrimp but know they have some special mineral requirements for molting and staying healthy. I've seen some put crushed coral in their tanks for calcium, but I haven't done so. I don't know my exact hardness or TDS but I suspect they are mid-range (have seen calcium/lime build-up on tanks allowed to evaporate). 

I do have the Hikari shrimp cuisine but don't feed it everyday since they're sufficient biofilm. My question is, how much calcium do they need? Are there other good sources than crushed coral? What about pulverized egg shells? What other minerals are important for shrimp health/molting? 

One of my RCS is turning a cloudy-white. I'm not sure if this is due to molting recently/preparing to molt or if they're not getting enough needed minerals. I know one molted very soon after being introduced to my tank because I saw the exoskeleton, but since then, I added them (there was 3 total) to a larger tank until I re-scaped their dedicated 5 gal shrimp tank. Because they're in a 33 gal with lots of plants and rocks, I hadn't seen them much but now this one seems to be out and about much more.

Not the best pics but gives you an idea of what I'm talking about. Thoughts?

Should I just add the crushed coral? Anything else?
 

Edited April 28, 2021 by Kalita

[darkG]

Magnesium is the other vital mineral. Chances are you don't need to add anything, your water (and food) may be providing it.

Edited April 28, 2021 by darkG

[Samanthabea]

Iodine (iodide? can't remember which one my test kits at home) helps molting they can turn whiteish when stressed or when molting or when they are old iodine is usually consumed in it's diet (very small amounts are needed I read) but it's also in the water some people say to keep levels good in the water and some don't it's a relatively new concept I never dosed mine and the shrimp were fine although some died from age I belive my ph was 7.8 and I added aquarium salt for my mollies shrimp usually hide when they molt for a few days after 

[Patrick_G]

I’d at least test GH for sure since it measures calcium and magnesium. I have soft water and I’ve used Wonder shell and Seachem Equilibrium. 

[Mmiller2001]

Here you go.