Fish Tank Plus, made by Technology 83 Systems Ltd.
Email info@technology83.com with what happened, your Windows version and your graphics card. A screenshot helps. We usually reply within two business days.
Open Fish Tank Plus and choose your scene and quality on the first page of Settings. The installer sets it up as your Windows screensaver; you can also pick it in Windows under Settings, Personalization, Lock screen, Screen saver.
Real 3D needs a webcam and camera permission for desktop apps (Windows Settings, Privacy & security, Camera). Sit in front of the screen with your face in good light. You can switch Real 3D off in Settings if you don't want it.
Lower the quality on the first page of Settings. Quality 1 is made for laptops with built-in graphics.
Yes: it plays in your phone's browser at play.fishtankplus.com, free, with nothing to install. Here's how to keep it on your Home Screen.
Yes. Under Multi-monitor setup, pick which screens show the aquarium and how thick your bezels are, and the picture lines up across them.
F feeds the fish, C changes the view, D cycles the clock, N switches day and night (open sea), E brings in a visitor (open sea), T shows your text, S shows the frame rate, Esc returns to Settings.
Windows Settings, Apps, Installed apps, Fish Tank Plus, Uninstall.
Privacy: how Fish Tank Plus handles your data.