How to build a self sustaining ecosystem
Choose a size for your ecosystem.
If you are new to building ecosystems, you may want to start small. However, the smaller your container, the harder it is to maintain a self-sustaining environment.

Larger containers allow for the inclusion of multiple diverse species and give everything room to grow. All containers must be clear to let in light.

How to make your guinea pig comfortable in its cage
Consider the size of the cage.
The humane society of the united states has noted that most cages available on the market for guinea pigs are simply too small. In fact, most cages are instead meant to house smaller animals like hamsters and gerbils.

Unlike other animals, guineas pigs need floor space, not vertical space. They need ample room to move around and exercise in order to stay healthy.

How to sell or swap gift cards
Use a gift card market site.
There are sites online that allow you to swap and sell gift cards, known as gift card marketplaces. These sites offer a balance guarantee on any card purchased or sold through them.

This ensures you are not scammed or given an unfair price for the gift card. They work as the middleman between buyers and sellers so you only deal with the company and not with any third parties.

How to increase mental strength
Read everything.
Recent studies show that people who enjoy reading novels are more easily able to empathize with others, a sign of a strong and well-rounded mind. If you want to work on increasing your mental strength, read a variety of things that you enjoy.
You don't have to jump straight into reading ulysses if you want to improve your mental strength, and in fact trying to read something too difficult might turn you off reading entirely. Instead, focus on reading things you enjoy.