Anybody know their stuff about building solar from parts/scratch?

Trying to price and put together solar parts from scratch. For a walipini aquaponics system. Struggling with the details.

You'll probably get more help with a more specific question.

Do you want to heat water, either for your fish or for heating the ambient air?
Do you want to heat air? (I'd say don't, refer to prior option.)
Do you want to generate electricity for your pumps?

Can you get even more specific than that?
What exactly is the problem you're trying to solve?