They don't jump per sey - at least mine have not - i have about 45 in 3 tanks. However they can get just about anywhere imaginable - i had one that loved the canister filter and kept squeezing between the grill and ending up at the bottom... They are also extremely fast when they want to zoom. They can jump but none of mine have.... if you have a HOB they are quite capable of getting in there - then again my female swordtail manage to jump into my hob several times...