First Time: I Bought Clams in London. - Do You Want Them as Pet or Food?

The first clams that I bought in my nine years in the UK. The Waitrose lady said "just wash and cook!". But I cleaned them just in case.

A few hours later... It seems no need to worry about sand. But what have they been eating? Water is dirty!!!

The next morning, I changed the water again. They look so much cleaner. 

They move and eject water a lot and I cannot stop looking at them!

A few hours later... Hummmm, the water looks clearer but the clams are still spitting a lot of dirt (or food???).

They were nearly becoming my pets, however; I had to complete my first "Carne De Porco Alentejana". 

My dear clam friends, you guys were so tasty. Don't blame me, but blame the Portuguese people who invented this lovely dish.