comercial food blocks, are they ok?

it's one of the recipes in the snail food sticky on top of the Inverts Forum :)

4 posts down, labeled Another Calcium Feeder Recipe
 
How long do the pucks last being vacuum packed? And it says that they last 2 weeks in the tank, does that mean that you just drop one in and you don't have to feed your inverts for two weeks or whenever the puck is gone?
 
Last in two weeks? Depends how many snails you have there and how acidic and soft your water is. The cana tank can have them for only a week. They just gnaw nonstop on the plaster of Paris pucks. The diffusas may keep them for 2-3 weeks. The pucks alone won't be sufficient diet for the snails. They can't stick to one food where they may not get other vitamins they need as they do with other foods. I put my other pucks in the fridge for longer storage and preventing mildew. It hasn't been humid in my place though but I err on the side of precaution or my efforts will be a complete waste. I'm conservative about my efforts.:)
 
(...) I still feed my snails Tums from time to time as they just love to bury their faces into the tablet and get their faces doused in white powder.:laugh:

Snail mustaches alone are good enough reason to feed Tums. They look so cute. :D
 
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