I would allow the water to circulate at least a couple of hours after adding the Metal Out before adding water. Did you add more water last night? Do you have more brown stuff on the bottom this morning? Hopefully you ran the hose into your skimmer to let the DE trap any metal that fell out of solution. I would suggest that you vac the sediment into your filter at this point, not vac to waste.

You should get at least a basic drop-based test kit. The strips are very inaccurate.

It sounds like you are on the right track. I know the DE filter clogs up quickly, but that is normal when you are trying to fight an algae bloom. Keep the cl level up until the cl level doesn't drop much overnight. The closer you keep the cl to 15, the faster your pool will clear up. If you let the cl level yo-yo up and down, it will take longer to eradicate the algae.

I wouldn't bother trying to adjust the other numbers until you get rid of the algae. The high cl levels affect some of the other tests, so just wait until you can allow the cl to drop to normal levels.