WHY IS MY AQUARIUM WATER CLOUDY?

Ever experienced water cloudiness? Guess what? You are not alone. All hobbyists have experienced cloudy water in their aquarium tank at some stage. So just what are the reasons that cause cloudy water in aquarium tanks?

Water clarity is usually related to age of the tank, as well as the level of care and maintenance provided. This article will help you identify the possible causes, along with some prevention tips and recommendations.

Residue from Rocks, Gravels & Substrates

Rocks, gravels and substrates have residues even when they are new from its packaging. Despite stating that they are “suitable for immediate use” on its packaging, it is always recommended for all gravels and substrates to be rinsed before use. “Suitable for immediate use” just means that no additional curing process is required; rinsing is still required.

If you are still experiencing cloudy water after the rocks, gravels and substrates are rinsed thoroughly, bacteria bloom could be the reason for it.

Cause(s):

• Residue from rocks, gravels and substrates

Symptom(s):

• White or grey cloudy water observed immediately when water is introduced during new tank setup

Recommendation(s):

• Rinse rocks, gravels and substrates before use
• Remove residues from using gravel cleaners and conduct water change to remove any other floating residues

Bacterial Bloom

A. Bacteria Bloom in New Aquarium

Bacterial bloom is a common situation experienced by hobbyists when setting up new aquariums, as it occurs during the early stages of the tank cycling process. During this process, beneficial bacteria build up in order to consume the ammonia being produced, hence causing the water to be milky. This cloudiness is caused by free floating beneficial bacteria which are not harmful for your fishes, and should go away when they settle down – usually takes about 1-2 days.

Note: Should your fishes be gasping for air at the water surface during this period, you can either conduct a 50% water change to reduce the amount of bacteria, or increase the supply of dissolved oxygen (e.g. introducing air pump).

Cause(s):

• Bacteria build up during the early stages of tank cycling process

Symptom(s):

• White or grey cloudy water observed after 3-5 days of new tank setup

Recommendation(s):

If fishes are introduced,

• Allow about 1-2 days for floating bacteria to settle and water will clear up

Note: If fishes are observed to be gasping for air at the water surface, conduct water change or increase air supply.

If fishes are not yet introduced,

• Allow about 3 weeks for tank cycling process to be completed before introducing fish

B. Bacteria Bloom Due To Sudden Increase in Nutrient Levels

The introduction of big quantities of new fishes to your aquarium tank or heavy feeding, even after tank cycling, will increase the nutrient levels causing ammonia and nitrite level to spike up. Ammonia and nitrite spikes can be deadly for your fish. Beneficial bacteria multiply rapidly to cope with the additional organic waste being produced, which in turn cause the water to appear cloudy.

The cloudiness usually last about 1-2 days till the water condition is stabilized. Introduce new fish gradually to reduce the impact in your aquarium tank.

Cause(s):

• Ammonia spikes from organic wastes produced by fishes

Symptom(s):

• White or grey cloudy water observed 1-3 days after large amount of fishes are introduced to tank

Recommendation(s):

• Introduce new fish gradually into your aquarium tank to prevent ammonia spikes

C. Bacteria Bloom Due To Restart of Beneficial Bacteria Colony

The beneficial bacteria colony residing in your tank can be removed, or even wiped out due to the following reasons:

• Introduction of untreated source water (which contains chlorine or chloramine)
• Introduction of medications (e.g. antibiotics)

The beneficial bacteria colony will attempt to rebuild itself when these occur, causing the aquarium water to be cloudy.

Cause(s):

• Introduction of chemicals that kill the beneficial bacteria colony

Symptom(s):

• Milky white or cloudy water observed 2-3 days after medication/chemical is introduced

Recommendation(s):

• Chlorine and chloramine is usually found in tap water; therefore water conditioner should always be used during water change
• Existing tank water, instead of tap water, should be used to wash or rinse filter mediums and ornaments to prevent unsettling the beneficial bacteria colony

D. Bacteria Bloom Due To Filtration System Shutdown or New Filter/Filter Medium

The tank water may also turn milky if the filtration system is being restarted after a long shutdown. The lack of water movement during these long shutdowns causes oxygen to deplete, which results in beneficial bacteria dying off and eventually turning the water milky.

Replacing your existing filter/filter medium will also result in bacteria bloom as the beneficial bacteria colony will attempt to rebuild itself when this occurs, causing the aquarium water to be cloudy.

Cause(s):

• Long shutdowns whereby bacteria dies off due to oxygen depletion caused by the lack of water movement
• Replacing established filter system/filter medium with new filter/filter medium

Symptom(s):

• White or grey cloudy water

Recommendation(s):

• Filtration systems should be always switched on and never turned off
• Mix 50% of the filter medium from the established filter with the new filter medium. This will help accelerate the cycling process

Filters powered by Hydro-Pure Technology (established tanks)

• Hydra Aquatic Depurator, Hydra Nano Plus, Hydra Stream (as an add-on filter)
  • Gradually increase operating hours to minimize impact on biological balance within the tank, as Hydro-Pure Technology converts nutrients as soon as water gets filtered (i.e. 8 hours for first week, 12 hours for second week, 24 hours for third week)
• Switching from other canister filters to Hydra Filtron
  • Replace at least 50% filter mediums with established filter mediums from previous filter to accelerate the buildup of beneficial bacteria

Other filters (established tanks)

• Always try to use the established filter mediums from your previous filter system to avoid starting a new tank cycling process

Algae Bloom

Whenever we see green cloudy water in your aquarium, it definitely means one thing – excessive floating algae growth.

A. Too Much Light

Like most aquatic plants, light encourages growth. This is usually caused by the aquarium being exposed to direct sunlight, or leaving the aquarium lights on for too long. Avoiding the placing of aquariums directly under sunlight and reducing the amount of time the lights are on will help solve the issue.

Cause(s):

• Aquarium exposed to direct sunlight or aquarium lights being switched on for too long

Symptom(s):

• Green cloudy water

Recommendation(s):

• Scrub away algae using algae scrappers and move aquarium tank away from being exposed to direct sunlight, or switch on the aquarium light for a shorter period

B. Excess Nutrients

Nutrients, such as phosphates and nitrates, supports algae growth. The possible sources of these additional nutrients includes decaying matters from uneaten fish food, fish excretes, dead fish and water source. Water change needs to be conducted as soon as possible to provide immediate relief, followed by removing the source of decay from the aquarium to completely resolve the problem. Providing good quality food in appropriate amount will prevent overfeeding and reduce fish wastes.

Cause(s):

• Excess nutrients from decaying matters from uneaten fish food, fish excretes, dead fish and water source

Symptom(s):

• Green cloudy water

Recommendation(s):

• Weekly water changes will help to reduce excess nutrients from water
• Remove source of nutrient, e.g. excess food and decaying matters
• Provide good quality food in appropriate amount to reduce amount of uneaten food
• Avoid overfeeding to reduce amount of fish wastes

IN CONCLUSION

From beginners to pros, it is inevitable for fishkeeping hobbyists to encounter cloudy water. Rather than feeling baffled on the causes, it is always good for aquarists to know learn and understand the possible causes, prevention and solutions for cloudy aquarium water. This will better prepare you when encountering similar situations.