Water is the key ingredient to successful freshwater tropical aquarium fish keeping. When you fill a glass with water and look at it… your first thought is the there’s not much to it. Wrong!
Water can be extremely complex. Water can contain several dissolved minerals, it can be hard or soft, it may have a high or low ph, it may be acidic or alkaline. If you have city water you probably have chlorines and fluorides in the water.
All this probably sounds pretty scary to the new aquarist! You’ll only need to worry about the complexity of your water if you are going to keep fish that are sensitive to water quality, if you intend to breed fish, or if your water supply is of very poor quality. Your local fish shop can test your tap water for you and give you a report on its quality.
The majority of fresh water tropical fish will adapt to your water quite nicely… if you acclimate them properly when you first bring them home.
Think about this for a minute! All of the tropical fish you buy have been in 3 or more aquariums, in different parts of the world, all with different types of water… and there still alive. Most likely when they get to your tank.. they will have it better than they’ve ever had it before.
The key factor to keeping a successful aquarium is stability. Your water supply doesn’t have to be perfect… the fish will adapt to what you have, providing its not off the charts. What your fish need is an constant even temperature, and weekly water changes of 10% to 20%… with out fail.