White glass

Here you will find particularly high-quality aquariums made of white glass.

White glass (also called "Low Iron" or "Ultraclear" or similar) is glass with a particularly low iron oxide content.
This makes it appear clearer and distorts the colours of plants and animals less than conventional (float) glass, which is why it has become the standard among discerning aquarists and aquascapers.

But it is a little more expensive.