You can go with a single camera connected to a wifi router (or wired) and typically an app on your phone to view it. That’s the basic version.
If you are more ambitious and/or already have a video security system, you should be able to add a dedicated tank camera(s) viewable from your phone as well.
Just know there is a very wide range of prices, function and resolution available. High resolution looks great but also requires speedy connections so it delivers smooth video/not jerky (due to dropped data). A color filter has been brought up. Be aware that there is a wide range of quality in CCD (camera) chips and optics used to capture the image itself. You might use multiple cameras to see both display & sump areas, for example. Another option is a PTZ (pan, tilt, zoom) capable camera, so you can ‘look around’. All in all, features cost money.
Be aware of security issues also. Especially if you plan to make your system viewable to others/publicly. You may want to run a VPN on your home network, if you don’t already, but that’s another discussion.
Best of luck. I hope you will share whatever you end up with, as there are likely others thinking about the same thing and/or would be interested.