1. It is not recommended to keep your aquarium where it receives direct sunlight. Exposure to direct sunlight can upset the balance of the aquarium and can raise aquarium temperature levels. It is best to keep your aquarium in a place where you can control the lighting.
2. It is generally a good practice to purchase the largest aquarium that you can actually afford. A larger aquarium will be less susceptible to quick changes in the chemistry, and will offer much more stability.
3. Cichlids tend to be very intelligent fish. You should do your best to interact with them as some species will respond positively to you arriving home. These fish are very active and if you interact with them, they can develop much better.