Newbie 75 gallon

[gregzz4]

Concerning your hammer; it's still looking OK even if it's not very big right now.
After that powerhead failure, I'd be inclined to run more carbon and change it every few days for 2 or 3 more batches. Make sure you rinse it very well before adding it to your tank.
About your pump, do you have anyone close to you with a multimeter?
I'd suggest you test the power supply for proper output.

Good luck