Float Test Tells You Little

Dropping seeds in water to see which sink is repeated constantly and predicts almost nothing about whether they will crack. Dark, striped, heavy looking seed also fails regularly, while pale small ones sometimes grow the best plant in the tent. Why these appearance based tests hold up poorly is explained at https://breederregularseeds.com. Soaking for more than a day to run the test can drown a seed that would otherwise have been fine.