Confused about my wallet

I'm new to Ethereum and I'm really confused. I am mining to my my Eth address and when I check my address at https://eth.nanopool.org/account/0xADDRESS I see how much ether I have mined so far. But when I check that same address in my GUI wallet on my Linux desktop 'Ethereum Wallet' it's showing 0.00 ETHER. Why is the same address showing 0.00 on the GUI desktop wallet but 0.05....... on the mining pool's website?

I don't remember if I got the address originally from CLI geth, https://www.myetherwallet.com/#view-wallet-info, or the desktop Ethereum Wallet.

Thanks.