Everything you care for in your household should earn its keep, right back at you. And while I cannot vouch for your spouse or children pulling their weight, your pets and plants will!
You can add your used, stinky fish water to your houseplants, lawn and garden for huge, shiny foliage, thriving blooms and tasty fruits. Add any dead fishies to your soil, buried deep in your flowering plants, or feed their bodies to your larger, carnivorous fish. I feed my dead bettas and barbs to my Oscars, and have a constant supply of my own feeder fish, from the millions of guppies that propagate in my guppy tanks. Callous? Insensitive? Nope, just keeping the cycle of life alive.
Guinea Pigs and Pocket Pets
If you have a pet in a cage, place used bedding - full of nutritious poops - in your garden as mulch, around trees, or in the compost bin. This includes newspaper, wood shavings, any natural litter or those new products like Critter Care and Yesterday's News.
I also have a small yard plot where I grow clover for my guinea pigs. I simply bought a small bag of seed, scattered the seed and added water, then let nature take over. Since clover grows like a weed, make a little fenced in area. Pull what you need daily, and dry extra boughs in your garage, or closet top shelves. I have harvested enough clover to last me all winter, without having to buy those expensive hay mini-bales.
I enjoy that I can close the loop with my piggies, from the garden (clover), back to the garden (mulch from their bedding).
Guinea pigs and other rodents are also great recyclers. All my used cardboard toilet paper and paper towel rolls go into their enclosures, as toys, and to help keep their teeth healthy. They love used paper bags to hide and play in. Easy, cheap toys! And one less thing to waste, ultimately. While you can recycle these items, it's better to just toss them straight back into the loop.
Dogs guard your house, family and belongings, eat your scrap food, catch mice (many dogs do this), and lower your blood pressure while at it. When you brush out your dogs, you can toss the hair right into your compost or worm bin. Studies have shown dog owners live longer and carry less stress in their lives, a great intangible bonus to caring for the family pet. Humans have maintained a friendly covenant with dogs since the Pleistocene...we are lucky to have them.
Cats also catch vermin and lower blood pressure/stress levels. Their urine marking also keeps other pesky animals - like raccoons, skunks and badgers - off your property.
A green plant provides moisture to the air in drier climates, and remove gaseous toxins from your home. As they breathe, they trap and remove dust particles and many air-borne allergens. The healthier the plants, the more benefits you get. Don't forget to add that fish water!