If you have a pet, chances are you've made one or two late-night runs to the store to grab food or litter. Pet lovers, there's a better way!

PetSmart is taking an extra 20% off select pet essentials when you choose to auto ship a subscription, which also nets free shipping. (The 20% off falls to 5% off on future shipments, but the convenience doesn't drop.)

Here's six pet subscriptions that'll make your life easier today.

6 Subscriptions You Need From PetSmart

Protein for Your Pup

Nature's Variety Instinct Dog Food Topper 14-oz. Bag for $22.39 via auto ship (a low by $5)

Dry dog kibble is convenient, but it wouldn't be part of a dog's natural diet in the wild. This mixer provides a boost in protein made from the kinds of foods dogs would consume without human intervention, and it's presumably delicious to canine palates.

Fruit for Your Feathered Friend

ZuPreem FruitBlend Large Bird Food 12-lb. Bag for $29.91 via auto ship (a low by $1)

Trix are for kids, but this lookalike blend is made especially for parrots. The combination of bananas, oranges, apples, and grapes gives your bird variety both in flavor and nutrients — which is important for optimum health.

Terrain for the Tank

All Living Things Hermit Crab Calcium Sand 2-lb. Bag for $4.79 via auto ship ($1 off)

It's called hermit crab sand, but this substrate is also suitable for lizards, spiders, snakes, and scorpions. If you have any of those desert-dwelling creatures, resist the urge to skimp on replacing its sand. Maintaining a hygienic living environment is important! (Just imagine if you never cleaned your house.)

Vibrance for Your Fish

Omega One Cichilid Super Color Pellets Fish Food 8-oz. Jar for $8.23 via auto ship (a low by $4)

Cichlids are one of those cool animals whose brilliant colors can be enhanced by what they eat. And these sinking pellets don't cloud the water like flake food sometimes does, which will improve your view of your now extra-bright fish.

Snacks for Small Creatures

All Living Things Natural Timothy Small Animal Hay 96-oz. Bag for $14.39 via auto ship ($4 off)

To rabbits, chinchillas, and guinea pigs, fresh hay is a treat, and they deserve some every once in a while. How sad would you be if you never got to eat chocolate (or chips, or whatever's your snack of choice)? Really sad, probably, and nobody wants to be responsible for making a fluffy little creature unhappy.

Drinkable Treats for Your Kitty

Whiskas Cat Milk 3-Carton Value Pack for $3.19 via auto ship (a low by $1)

Cats love milk, but it can be hard on their digestive systems. Hence the invention of this special beverage, which allows you to indulge your feline pal's dairy cravings without fearing that you'll trigger an upset stomach.

Readers, what pets do you have? Are you planning to set up any subscriptions at PetSmart? Let us know in the comments!