redearslider.com

I just got my red eared slider last Christmas.

She spends the majority of her time in the water.
In fact I rarely see her in her basking spot (which is easy for her to get to)

Recently a pet store owner told me she should be spending the majority of her time out of the water, and only in it occasionally to eat and poop.

I started taking her out of the water and she HATED it.
So I keep her in her tank now to stop from stressing her out.

But my question is, (and I've heard conflicting information) is it ok if she stays in the water most of her life?
Or do I need to take her out from time to time?
If so how long?

RES are aquatic turtles so they do spend a significant amount of time in the water. That being said, it is vital to your turtle's health that she bask regularly. What are your water temps and your basking temps? If the basking area isn't a fair amount warmer than the water (roughly 10degrees F) then your turtle may not get out to bask enough.

RES are aquatic turtles and will spend about 80% of their time in water. They do, however, need a good basking area as well as a UVB light and heat light to bask under. A basking area temp in the range of 88-90F is good, with the water temp about 10 degrees cooler to give the turtle an incentive to bask for the warmth. Getting out of the water and drying off under the above-mentioned lighting is important for the health of the shell (and UVB rays are needed so they can be metabolized into Vit. D3 to aid in calcium absorption).

The pet store owner is misinformed regarding the requirements of RES.

They pets store guy is wrong. Yertle spends 30% of his time in water and 70% out of water. But Savava is the opposite.

If your RES wants out she will get out. And the rest is exactly like Marisa and Megcornell said.