Ok you guys convinced me...
 

I bought Goldfish Aquarium today and it's great but I have another question. I change the background settings and nothing seems to change. How do you change the amount of plants and get it to take right away? Thanks for everyone's help and the screens and everything.

There are multiple tanks available for individual configuration and viewing. Some tanks have more plants than others, some no plants at all.

If you press the H key when the aquarium is running it will show you available shortcut keys that will prove helpful.

Pressing the space bar will present the options panel as well.

The [ key and the ] key allow you to scroll through the tanks while the aquarium is active and any settings you change to the individual tanks are saved for that tank when you click the OK button.

Attached find the shortcut panel presented when you press H while the aquarium is running.

There is a bug (Prolific claims a lack of documentation) but the "selected" item in settings >Tank configuration is what will open the next time around. The "check" marks are there just to confuse us.
Lacking in clarity might be one way to put it...

Yea I found the settings to be a bit confusing but got them figured out finally, thanks. The tanks are really nice although I mostly just prefer the standard tank.