Hi Beto. We're sorry you're having a tough time with your brick. Brick is very absorbent and can wick moisture or retain vapor residues, such as oils or tannins. Manganese is probably the most common stain on brick because it happens at the manufacturing stage when the bricks are exposed to acid during production. Unfortunately, this outcome is tough to see on raw brick or stone and can’t be predicted before or during the application of any paint product. We do have solution in cases where this happens. Reach out to our team at info@romabio.com.