What causes these brown/gold tips on the leaves?
The white material is Sevin Dust.
First: Welcome to the forum @Flounder6900 
Second, usually burnt tips are signs that you are pushing the nutrients to the max… But there’s also spots on the body of the leaves, so it might be something else. Let’s ask some great growers… @Budbrother , what say you?
And you Monsieur @Growdoc ?
The ends look like he’s at max on EC , if the edges turn as well, it’s potassium deficiency. The sevin looked like WPM, glad he clarified.
The spots on leaves looks like nute splash, but overwatering when young can cause leaf spots between the veins as well. Those look like nute splash….
Also what I think… 
The white spots are from Se,vin Dust.
Have been pushing nutrients will flush soil and slow down a little.
Thx.
I realize that. @Growdoc meant the yellow spots in the middle of the leaves looks like nutrient splashes…
I’ve never seen 7 dust do any kind of plants less put on when sun out
Look close, the small white spots are the Sevin dust, it’s just deposited on the leaves, no damage from it, although I wouldn’t use sevin, but Deadbug or Spliven instead.
I agree with you @Growdoc I use to though i use dead bug also and fly strips do you remember the blue dragon
Welcome to ILGM @Flounder6900
Welcome to the forum @Flounder6900 ! You won’t find any better advice from anywhere else! Looks like the knowledgeable growmies have you covered. As said by @Growdoc there are better canna friendly options for getting rid of pest for sure. Some are safe to use til harvest!
Yes sir, and then it came in a 5 lb bag!
Welcome to the forum @Flounder6900 very helpful and knowledgeable growmies here they wont steer ya wrong​
What is better than 7dust.
I’m old school.
@Budbrother put me on beauvaria bassiana, jacks deadbug is good as well.
Dead bug as @SausageMahoney saying but spider mites haven’t found anything that will kill them gone. They are a fight they are mother if you know what I’m saying 
You get SM again, get some Deadbug and tag me, I’ll walk you through eradication it the lil bastards!
Ok @Growdoc buddy they are something else and they bad down around these mountains
I got them a few times on back, but found a way to get them gone!
One of the hardest things I ever try to get rid of I’ve had them twice myself @Growdoc