Recommended anti-spam

Hi, my client has just put in a new form using ‘insightly’ instead of contact form 7. Now they’re getting lots of contact form spam, as obviously my cf7 honeypot no longer stops it. I have akismet in place, but that isn’t stopping the form spam.

Can you recommend a plugin which could help stop contact form spam? Something light and reliable and ideally without captcha.

Thank you.