Potty training for rats means litter training, and the sooner you begin, the better your rats will be at it, although older rats have been known to catch on quickly as well.
The key is going to come down to sounding a stimulus and giving a reward to reinforce good behavior. More on that in a minute, but first it's important to understand a rat's instincts.
A rat will instinctively leave solid waste in a corner of their enclosed dwelling, making it easy to transition them to using a litter tray.
Urine, however, is an entirely different story. Many rats, especially males, will pee all over the place in little droplets. It's a way of marking their territory and even a sign of affection. They pee on the things they like – their food, each other, and you! You can always keep an old towel or rag around to wipe up any "token of love" they leave around.
The idea of potty training is, at the very least, to get your ratties to leave all their solid waste in one spot that is set apart from the rest of their lodging. Not only does keeping everything clean mean much less work for you, but it also makes the place less germy, keeping your precious pet rat as healthy as possible.
Step 1. On cage clean-up day, notice where most of your rat's solid waste was deposited. With gloves on, pick up their solid droppings and put them away.
Step 2. Prepare a corner ferret litter tray (available at any pet store) with a plastic lining and then fill to about an inch to two inches from the bottom with some ferret or kitty litter. Add the droppings.
Step 3. After cleaning the cage completely, place the prepared litter tray inside the same corner of the cage where your rats tend to leave droppings.
Step 4. When your rat gets the idea and begin to use the litter tray, sound a stimulus (a unique sound you make like cooing "good boy!" Or "good girl!") And reward them profusely. Be sure to praise them with hugs and kisses, too.
Step 5. If you see your pet rat "missing the target" you can try to move them, or at the very least, move the dropping into the tray immediately.
Step 6. Take the time, at least once each day, to move fresh droppings into the litter tray. Sometimes your quick-witted friend will notice how much cleaner and fresher the air places when they poop in the right place.
It is also a very good idea to allow your pet rats access to a litter tray during their playtime. This would mean either keeping the entire cage accessible to them with the door open, or placing the tile in one corner of their play space.
With encouragement and rewards for good behavior, your pal will be potty-trained in no time at all.