17 Point Checklist For Aquarium Water Treatment, a must have guide for homemakers

From sources of water to various chemicals in water. Know all about the water to use for your aquatic culture to thrive.

What do you mean by aquarium water treatment?

Managing aquarium like aquaculture is delicate but tedious task. Your efforts not only ensures the survival of the fishes but also their mood and metabolism. Hence it becomes very important to control the quality of water in order to sustain the aquatic life and the way to do so is by aquarium water treatment. 

Maintaining an aquarium is no easy task. Factors are innumerable to consider. You need to understand that it is an entire ecosystem that you are preserving. This ecosystem controls its inhabitants:

  • Survival
  • Metabolism
  • Reproduction
Aquarium maintenance

Aquarium may look to us, a glass enclosure with few beautiful biotic elements but for the living beings that reside in it, it's not just a home but the entire environment to them.

Why is aquarium water quality so important?

Water that flows inside the aquarium is the most important element shaping their behavior. It contains minerals necessary for survival if present in optimum quantities. Hence it is important to control the quality of water to be used in our aquariums.

The chemicals that affect the fishes and other biotic elements may not always come from outside sources. For instance, fish waste and other decomposing material will result into production of ammonia. This ammonia in high quantities, may kill biotic elements in an aquarium.

Over feeding is also one factor that may result into causing elevated levels of ammonia and nitrite in aquarium. It should be corrected immediately.

Summarizing the factors affecting aquatic life in your aquarium:

  • The source of water used
  • The food you feed your fish
  • The amount of algae growing
  • Chemicals in water
  • Water quality parameters such as hardness, pH
  • Temperature inside the aquarium.

At Urban Aqua Care we cover all the above topics except food for the fishes. This website aims to purify water for every urban use possible. Covering feed for fishes is beyond the scope of this website. 

Sources of Water

Water that flows into the aquarium comes from many different sources. Due to this difference in sources, the quality of water also varies. Let us summarize some of them : 

Municipal/Untreated tap water

Municipal water is often treated with chlorine/ chloramine for the purpose of disinfection. Chloramine is chlorine bonded to ammonia, both of which are harmful for fishes even in minute quantities.

As we know chlorine is toxic to even humans let alone fishes. It needs to be eliminated. Aeration is helpful in eliminating chlorine. Later down the segment we will discuss its elimination in detail.

Well water

Well water varies geographically. Depending on the region, well water generally may lack :

Dissolved Oxygen

Well water could be rich in:

Dissolved carbon dioxide
Dissolved Nitrogen
Hydrogen Sulfide
Aeration can help rectify the quantity of all the above elements. Heavy aeration can even help eliminate hydrogen sulfide(H2S). It also allows dissolved iron to settle down as rust, which can then be separated from water.

To ensure the survival of fishes, well water should be tested for other water parameters such as pH, alkalinity, hardness. Simple commercial kits are available for testing all of these parameters. 

Reverse Osmosis (R.O) water

Reverse osmosis is a physical method of water purification. Water is forced through a semi-permeable membrane. This results into water molecules being fine in nature to pass, leaving behind many of the impurities such as heavy metals, minerals, phosphates, nitrates and other dissolved solids thus separating them from water.

R.O. water is not always a good choice for it lacks many essential minerals needed by fishes to survive.

Softened water from hard water

Softened water has more of sodium ions which replaces mostly calcium and magnesium to remove hardness from water. The aquarium plants and fishes prefer soft/hard water depending on their native place of origin. For example, those that come from Amazon rainforest (waters with very low hardness) will do better in soft water. But it is not with all the categories of aquatic flora and fauna.

Identifying the Chemicals in Aquarium Water

As discussed above, here are the various possible chemicals that can be found in aquarium water.

Chlorine and Chloramine

Tap water supplied by municipality is generally treated with chlorine or chloramine to make it safe to drink. Post disinfection they may still remain in water in minute quantities. Minutes quantities of these chemicals are safe to humans but when it comes to fishes it can be fatal to them. They are toxic to fish gills and invertebrates.


Ammonia (NH3) is toxic to fish. It enters water through excretion by the gill membranes of fishes. This introduces nitrogen into the aquarium. There are certain other factors that may cause ammonia levels to rise:

  • If fish dies and is not promptly removed
  • If the filter fails for a period of time
  • If the tank is not well maintained 
  • Prolonged power outage


Using a Tetra Easy Base can help solve the problem. For dosage and concentration of the solution check out the Tetra Easy Base.


Increasing aeration with an air pump and air diffuser helps reducing the level of Nitrite. Using Tetra Safe Start is also recommended.

Using aquarium salts can help avoid the effects of nitrite poisoning. Adding salts in small quantities helps benefit the freshwater aquariums.

Caution: Scaleless fish, such as the catfish family, do not tolerate salt well. Live plants are also generally intolerant of salt.

Water Quality Parameters

pH levels

There are many pH adjusters available. You cannot simply buy simple acids and bases to lower or raise pH. This is because most products are buffered to a specific pH. You must realize that sudden change in pH is very harmful. Besides if your water is highly alkaline, it means it has a lot of buffering capacity. Adding any acid may lower the pH but it will bounce back again, no matter how much of the product you add.

Using Tetra Correct pH can be used. Calcareous sands and gravels can also be used to increase the pH and buffer the water. Crushed coral if used will slowly dissolve in acidic conditions, neutralizing acid and increasing buffering capacity.

Remember it is more easy to increase the pH than lower down the pH value.

Total Hardness or GH

Most fish can live in a wide range of GH, but some species may be more sensitive to changes in GH. Check out the dosage and solution of a GH regulator.

Total Alkalinity Carbonate Hardness or KH

Carbonate hardness or KH is the measure of carbonates and bicarbonates in water. Appropriate KH levels will help to stabilize pH levels in the aquarium. With regular partial water changes using tap water KH will usually remain at a good level.

Using a Tetra EasyBalance Solution can help solve the problem.

17 Point checklist for Aquarium Maintenance



Run a newly set up aquarium for 48-72 hours before making your first fish purchase.

Never leave the aquarium light on for 24/7. This would not only lead to excessive algae growth but also stresses your fish. 

Aim for larger aquariums as they are more stable and easier to maintain.

Don’t destroy the interior of your aquarium to clean it. For this will eradicate the biological balance of your aquatic ecosystem.

Have your tap water tested for pH, alkalinity and nitrate to make sure it is ready for aquarium use.

Never place your aquarium near a sunny window or near an air conditioner. Maintain stable temperature.

Research the right food, environment, temperature and skills required to maintain the biotic inhabitants.

Never buy those fish which can outgrow your tank or get in conflict with existing tank inhabitants.

Always treat tap water with a water conditioner to neutralize chlorine, chloramine and ammonia before adding it to the aquarium.

Don’t forget the size of your aquarium before buying a large number of fishes.

Make sure to change filter cartridges regularly once every month.

Never feed your fish more than it can consume. Uneaten food can pollute the water.

Regular inspection of your fish for health is a good practise.

Never remove a heater from the water if it is still turned on. Unplug it first, let it cool and then remove it.

Remember not to change more than 10% of your aquarium water every week or 25% every two weeks. 

Feed your fish a variety of flake, pellet and frozen foods to make sure they are getting proper nutrition.

Replacement water should be the same temperature and pH as the aquarium water.