While there is plenty of life in Silfra, most of it is invisible to the human eye – unless you’re talking about plant life, of course. Bright green, twisting “troll hair” grass grows at the bottom of the chasm and there are loads of unseen microscopic invertebrates.
There are three types of fish that live in the Þingvallavatn lake that feeds into the Silfra fissure – brown trout, sticklebacks and Arctic char. Only the Arctic char ventures into the fissure and only during mating season in July and August.
The only fish you might spot in the fissure itself is the dwarf char, but these are very small and tend to lurk in hidey holes and dark spots. Spotting a dwarf char is rare.