Can't see the tank at all
I'm interested in that co2 system, i'll have to go look at petco.
Also goldfish require much much larger tanks then anyone gives them credit for. They produce 4x the waste per inch of a normal fish and they get up to 12"
Unfortunate misconception of the hobby.
Look into whiteclouds for a small unheated tank, they look great and will be happier then the goldfish.