The lake has to be the cleanest large body of water in Europe. It 'ages' a little over the season but in spring it is drinkable without problem. Its reed-beds are home to colonies of freshwater sponges, which act as filters. Balaton is clean but not clear: most of the rivers that feed it come in from the north through soils that are partly chalky, partly volcanic resulting in turbulent pea-green water under many lights.

A significant part of the lake’s flora consists of algae. The most common types of pondweed are water spikes. Reed grass, sedge and bulrush continue to exist in the Northern part of the lake.

Beyond the numerous bird species and the about 50 species of fish, fauna is represented by protist creatures, the above mentioned freshwater sponges, crabs and mussels.  

The following fish species can be found in the lake: carp (ponty), wels catfish (harcsa), pikeperch (fogassüllő), Volga-pikeperch (kősüllő), aspe (balin), pike (csuka), eel (angolna), grass carp (amur), silvercarp (fehér busa), breams and it's specialty, the razor fish (garda). There are also European chubs (domolykó) and tenches (compó) and in Kis-Balaton you will find European mudminnows (lápi póc).

The main bird species living around the lake are anatidae, including mute swan (bütykös hattyú) which has proliferated here during the last two decades, black-headed gulls (dankasirály), common terns (küszvágó csér) and cormorants (kormorán/kárókatona).

More than 1200 species live in the water and its surroundings. In the nearby forests red cicadas, smooth snakes, ravens, dunnocks and coal tits make life more colourful but hikers may also spot red deers, foxes and fallow deers. The saker falcon is a real rarity. Forests range from oak to pine. Beside bird's-eye primrose, which is the emblazonry of the Balaton Uplands Nature Reserve, several other beautiful flowers such as yellow pheasant's eye, small pasque flower and burning bush adorn the landscape.