Additives

Additives are liquids or powders you add directly to your aquarium water to make it safer or healthier for your fish and plants. They’re a handy part of the hobby because they let you adjust water conditions, treat problems, or give your plants an extra boost when needed. The most important additive for almost every aquarist is a dechlorinator, which makes tap water safe by removing chlorine and chloramine - without it, adding untreated tap water can harm or even kill your fish. Other common additives include bacterial starters (to help cycle a new tank), fertilizers for planted aquariums, and treatments for fish illnesses. Most additives come with droppers or measuring caps so you can dose them accurately. It’s worth keeping a few basics on hand, especially dechlorinator, so you’re prepared if something unexpected comes up.