Changing the water in an aquarium is an important task that helps keep the aquarium environment healthy and suitable for its inhabitants. Regular water changes remove excess ammonia, nitrite, and other toxic substances that accumulate in the water. This is essential for the healthy development of fish and aquatic plants. Knowing how to change aquarium water can greatly improve the quality of life for the aquarium’s inhabitants.
Based on my many years of experience, I have outlined a well-planned method for changing aquarium water, which I hope will be of great benefit to both new and experienced aquarists.
Advance Preparation
Prepare the water: Prepare the water for the tank 24 hours before performing a water change. Regular water contains chlorine and other heavy metals that are harmful to fish, so use a water conditioner to remove these elements. Ideally, the pH, ammonia, and other parameters of the prepared water should match those in the tank. The temperature of the tank water and the prepared water should also be similar. You can place the prepared water near the tank to help achieve this.
Gather the necessary equipment:
- Siphon or gravity vacuum
- Bucket, mug
- Thermometer
- Water testing kit (pH, ammonia, nitrite, and nitrate)
Unplug electrical equipment: 4-5 minutes before changing the water, unplug the heater, filter, lights, and other electrical equipment from the aquarium. Pay special attention to the heater, as removing water while the heater is plugged in can cause it to burst. Additionally, changing water while electrical connections are still active can result in accidents.
How to change aquarium water
Water Change
The tube on the gravel vacuum or siphon will go into the tank, and the flexible pipe will be outside the tank, through which the water will drain. A bucket or container should be placed outside the tank so that the water from the tank can collect through the tube and be put into the bucket or container.
If there is debris on the gravel in your tank, after turning on the vacuum, clean the inner tube by rotating it around the sides of the tank over the gravel. Use a special aquarium spoon or stick to gently stir the waste where it has settled, so that the settled waste can rise from the gravel and be sucked out with the water through the vacuum tube.
The vacuum tube should be kept 2 inches (5.08 cm) away from the base of any live plants in the tank to avoid damaging the roots. Plants love organic waste and get nutrients from this waste within a 2-inch (5.08 cm) radius.
Add New Water
Before adding new water to the tank, it is especially important to check the water temperature with a thermometer and other components (pH, ammonia, nitrite) using a water testing kit. If everything is fine, slowly pour the water you prepared in advance into the tank from a mug to avoid disturbing the gravel and scaring your fish.
Plug-in Electrical Equipment
After adding new water, place all electrical equipment in the designated place in the tank. Plug in and especially turn on the filter so that if there is any dirt in the water, it can start cleaning. Then turn on everything as needed.
Water Change Time and Amount
In general, it is better to change the water every week. If this is not possible, then changing the water every two weeks is acceptable. During the water change, 15-20% should be replaced for small tanks (15-20 gallons) and 25-40% for large tanks (20-40 gallons or larger).
More than 50% of the water should not be changed, as there are plants and many types of beneficial bacteria in the water. If you change all the water in one day, the beneficial bacteria will be washed away, which is harmful to the plants and fish.
Sometimes fish have various problems or become sick, in which case a water change is necessary. It is advisable to consult a good veterinarian before making any significant water changes.
Can fish be kept in the tank during a water change?
From my experience, there is no need to remove the fish from the tank during the cleaning process. In fact, it is better to leave them, as moving them will stress them at best and can even hurt them at worst. I clean gently and carefully around them as I work.
Why do I need to change the water?
When feeding the fish, many excess food particles fall to the bottom. The fish release this food into the water as urine or feces. The dead or torn parts of the plants in the tank decompose, increasing the levels of nitrates, ammonia, and phosphates, which promotes excessive algae growth and reduces oxygen levels. This, in turn, stresses your fish and can even make them sick. It can be observed that fish suddenly become ill, and several water changes may be needed to treat them.
Additional Tips:
Since you have unplugged the electrical equipment to change the aquarium water and have drained some of the water from the tank, you can clean the tank, plants, rocks, and decorations if you wish, so that you don’t have to clean them again later.
Tank Cleaning
Tank Cleaning
The easiest way to clean the inside glass of a fish tank is to purchase a fish tank cleaning brush. It removes the toughest algae without straining. This is definitely the best way to clean the glass of a fish tank. There are scrapers, power scrubbers, and a variety of expensive gadgets that can be used to clean the inside glass of an aquarium completely.
Tank Plants Cleaning
Take the plants out of the tank, trim off the unwanted parts of the plants with a pair of clean scissors, and wipe the algae off the plants with a damp paper towel. Gently rub the algae off the leaves of the plants so as not to damage them in any way. This is very delicate work, and some of your plants will be damaged. Remove any damaged leaves before returning the plant to the tank.
Cleaning Aquarium Decorations
Remove the decorations from the aquarium and soak them in a bucket of vinegar solution for 20-30 minutes. Then, remove them from the vinegar solution and scrub them with a new toothbrush or a clean, damp cloth. After that, rinse them with clean water, dry them, and put them back in the aquarium.
Cleaning gravel
Gravel
If there is tough algae, I use bleach, and if there is no tough algae, I use vinegar. However, I never use bleach in an aquarium. I soak the rocks in a bleach solution of 1 part bleach to 20 parts water for 10-15 minutes. If there are tough stains after removing the bleach, scrub them with a clean, new toothbrush to remove the dirt, rinse them well with clean water, dry them well, and put them back in the aquarium.
