Smart Swithing

how can i define my mikortik router to switch to other ISP when the 20% of my 1st ISP is used??
Please tell me is that possible ? If yes !
So tell me the procedure of this…!

https://wiki.mikrotik.com/wiki/ECMP_load_balancing_with_masquerade#Routing

You can use asymmetric bandwidth links also - for example one link is 2Mbps other 10Mbps. Just use this command to make load balancing 1:5

/ ip route
add dst-address=0.0.0.0/0 gateway=10.111.0.1,10.112.0.1,10.112.0.1,10.112.0.1,10.112.0.1,10.112.0.1 check-gateway=ping

https://mum.mikrotik.com/presentations/US12/tomas.pdf

I followed this and it works like magic.