jm \Tq^4OÝã½Lq×ORÏê&ѤåL¬The maximum you can send is the number of satoshis in your memo address minus the fees required. Unfortunately there isn't a feature for calculating that automatically yet.
https://whatsonchain.com/tx/614c4fb23008a5096b329b803e6a062d8886f13baa8f95d72e8e89dde7ecc345