I used pallets for all the built. Removed all the nails and used only the wood from the pallets. I didn't bought anything only screws and hinges.
The stain was done by using a mix of different vinegars (white, red wine, apple cider) and steel wool. After different time of resting, of cut it with water to be able to control the tone of each color using a cheap brush to apply it directly on the wood. No sanding was done to keep the wood look more rough.
Made 2 opening doors on the front, and removable panels on the sides, kept the back open for evacuating heat from filter, air pump and air circulation for humidity.