Fuse on power wire popped, what can I do?

Just had it put in 2 days ago. The power wire to the battery has the inline fuse holder with a 20 amp fuse that popped. I run 2 amps, MTX 200 watt and Jensen 600 watt.

What amp fuse should I use? What can I use safely? I'd imagine a 40 would not be an issue.

 

What size wire is it?

The fuse is to protect the wiring and the truck... not the amp.

But 800 watts on a 12v system is almost 70 amps. You need a 100a breaker and #2 cable all the way from the battery to the amps and on the ground.
You could get away with a couple of 65a fuses on two separate runs of #6 hot and ground or a #2 ground.

Do not just put a larger fuse in the fuse holder unless the wire is large enough to carry the load.

 

uhh 800 watts is ~66.6 amps

edit: rich beat me to it

 

It's either 4 or 2 gauge, not sure off my head. I tossed in a 50 amp and no more issues.

 

If your truck were to burn, the first thing the insurance adjuster is going to check is aftermarket wiring sizes, fuse types and ratings, and installations. If not to manufacturer's recommendations, no payment. It is all about liability avoidance.