My biggest turtle has been crawling on top of my second biggest one and shaking his hands at the other turtles head also stretching his own head out really far so that is will be close to the bottom turtles. Could this be a mating thing?

The shaking is called fluttering and is a sign of aggression. Have you sexed your turtles yet? What size are they and how big is their enclosure?

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~Christi
1.0 Red Ear Slider: Mikey
1.0 Het for Albino Red Tail Boa Constrictor: Kaa
0.0.1 Northern Blue Tongue Skink: Petri
1.0 American Staffordshire Terrier/Lab: Brutus
1.0 German Shepherd: Pax
1.0 Husband: Will
“Life is as dear to the mute creature as it is to a man. Just as one wants happiness and fears pain, just as one wants to live and not to die, so do other creatures.”——His Holiness The Dalai Lama

The bigger one is three years old and five inches, the younger one is two and a half years old and 3-inches
The older one is a male and the younger one is a female.
The reason I ask if it is a mating sign, because someone told me that it was but I wasn't sure.
They are in a 20-gallon tank.
(I can't afford to spend a huge amount for anything bigger right now)

I can say with some certainty that it's aggression. Your turtles should be in a 65-80 gallon tank. If you can't afford an aquarium, that's okay. Rubber maid tubs, metal stock tanks (found at farm stores) are big enough and really cheap. You can get a 100 gallon stock tank for like $50 and that will house both of them. Or you can get a big rubber maid tub for the larger turtle. They cost like $15-$20. If you don't increase their housing size soon, the fluttering can turn into biting which can be lethal.

__________________
~Christi
1.0 Red Ear Slider: Mikey
1.0 Het for Albino Red Tail Boa Constrictor: Kaa
0.0.1 Northern Blue Tongue Skink: Petri
1.0 American Staffordshire Terrier/Lab: Brutus
1.0 German Shepherd: Pax
1.0 Husband: Will
“Life is as dear to the mute creature as it is to a man. Just as one wants happiness and fears pain, just as one wants to live and not to die, so do other creatures.”——His Holiness The Dalai Lama

ok thanks, yeah I was thinking about getting one of those stock tanks.

A friend of mine got a plastic stock tank for $65 at the local farm store. Holds 110 gallons, although they have it only 2/3 full with some land, but their turtles are very happy.

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My name is Liz
Do what's best for the animal, not what's best for you.