What should I use to clean my fish tank when considering the myriad of cleaning supplies and tools available in the market? Is it prudent to utilize chemical cleaners, or should I gravitate towards more eco-friendly alternatives that would safeguard my aquatic inhabitants? Are there specific brushes or scrapers designed for the delicate surfaces of aquarium glass that can effectively eradicate algae without causing scratches? Moreover, how important is it to consider the type of substrate when selecting cleaning agents? Should I be cautious about utilizing certain products that might disrupt the carefully balanced ecosystem that my fish rely upon? Perhaps I should investigate the effectiveness of natural remedies against stubborn stains. What about the filtration system in my tank? Could cleaning it with appropriate methods enhance its efficiency, or is there a risk of removing beneficial bacteria essential for water quality? In this context, what optimal cleaning routine should I adopt to maintain a pristine environment for my aquatic life?