Pokémon GO Replay: Water Research Day is coming on March 21 from 2 p.m. to 5 p.m. local time, spotlighting Lotad, Feebas and Clamperl along with their Shiny versions. The event includes themed Field Research, paid Timed Research and extra bonuses to make catching and completing tasks more rewarding. It’s a short but action-packed window for trainers to stock up on water-type Pokémon, hunt Shiny variants and complete event challenges. With a mix of free and paid content, there’s something for every player looking to make the most of Water Research Day.
Source: Official Pokémon GO blog