on DonaldCoin and all my site i use 4 simple captcha in one page i call it "Multi-Captcha Account Verify".
it's required only once after signup and when i want to force it every some days for all members.
when i feel there are some bots on the site, i force it again once for all members.
i advice all other faucets do same.
no need to have 2 captcha for every claim, but 2 to 4 captcha every some days is good solution.
solving 4 diff captcha correctly in same time is about impossible for bots.
and all captcha are very easy for users, no need to use complex ones or hard to read ones as like solvemedia.
I don't understand this - its required once after signup and when you want to force it. And than you say that bots can't solve 4 captchas. Than why are you forcing captchas every few days if they are impossible for bots to solve it in first place? Better fix your faucet, its kicking me out when i want to do something that includes opening in new tab, like collecting rewards, or gift, or coin parts
To OP, i think if bots want to take money from you they will, maybe its better solution to set withdraw limit and manually send coins to users