My cousin asked me to make her a beach theme baby shower cake. I'm looking at all these fabulous cakes here on CC for inspiration and I've noticed that some uses piping gel for the water and others uses BC. For the sand, some uses brown sugar and other uses graham cracker. What are the pros and cons between these choices? Why do you use certain things and why? Thanks for your insights!

I loved using a mix of brown sugar and graham crackers for my sand. Its very realistic and tastes good. You can cover a big area with no problems! Ive used both gumpaste and chocolate for making seashells. My gumpaste one's came out the most realistic. Ofcourse the chocolate ones taste better. If you swirl mild chocolate in your white it gives you a marbled effect which also looks nice. I made my own molds by buying a bag of seashells from Walmart and silicone plastique. I got a great variety of molds for cheaper than trying to buy molds individually which run around $25 a piece.
Depending on where your putting your water, would depend on what medium to use. Heat and humidity will make your piping gel stay kind of runny. So if its going to be outdoors use RI. Hope this helps!

Thank you!

Depends what look you want. You can create a sandy look by stippling fondant (there's a cake in my album on here which was done like that, if you want a visual). And you can create water using marbled fondant, then just paint it with something to make it shiny (either piping gel, or vodka).

I have used candy molds for the seashells and you can find them for about $2-$3 each.