Cleaning Your Aquarium of Bacterial Bloom

Fish Swimming In Aquarium

While most aquarium owners would prefer absolutely clean, clear water for their fish, unforeseen conditions may emerge that necessitate treatment. Bacterial bloom is a common occurrence: Bacterial bloom, also known as bacterial bloom, causes murky or milky water in your aquarium, which can make it difficult to view your fish.

What Is a Bacterial Bloom?

Bacterial bloom is a phenomenon in which the quantity of bacterial colonies, especially bacteria floating in the water column, suddenly increases. The bacteria multiply at such a high rate that they become visible to the naked eye, causing the water to seem murky.

This condition is most common in a newly established aquarium, but it can also develop in a tank when the nutrients in the water, notably nitrates and phosphates, have increased. This can happen if fish die and aren't removed quickly enough, or if plants die and aren't removed. Excessive feeding of fish without cleaning up the trash might result in a spike in nutrients and bacterial bloom.

Part of the Nitrogen Cycle

There are two types of bacteria at work in aquariums:

  • Autotrophic Bacteria: Bacteria capable of synthesizing its own food from inorganic substances, using light or chemical energy. The beneficial filter bacteria are autotrophs.
  • Heterotrophic Bacteria: Bacteria that cannot synthesize its own food and is dependent on complex organic substances for nutrition. The heterotrophs in the aquariums mineralize the organic waste (break down the uneaten food, fish waste, dead plant matter, etc. into ammonia).

It is more common that the heterotrophs are seen in bacterial blooms, not the trusted autotroph nitrifiers.

It is the heterotrophs that are primarily responsible for creating the "bio-film" (slimy residue found on the tank walls and ornaments) which builds up in the "new water" aquarium.

Heterotrophs are usually larger than autotrophs, and so do not attach themselves to surfaces as readily. They also reproduce at a considerably faster rate. Autotrophs can take up to 24 hours to reproduce, but heterotrophs can replicate in 15 to 20 minutes.

The heterotrophs begin to work faster than the autotrophs in a newly set-up aquarium, resulting in the common "cycling bloom." Blooms that are created by a build-up of organic waste in the substrate, which most, if not all, are, are almost definitely heterotrophic.

Bacterial blooms are widespread in tanks that appear to be devoid of organics (for example, where all that is in the tank is water and ammonia for a fishless cycle). This is produced by the abrupt dechlorination of the water, which allows bacterial colonies to thrive. The heterotrophs set to work right away on the organics in the water. The amount of organics in the water supply determines the intensity of the bloom, as well as whether one occurs at all.

The Effects

Because the aquarium is an oxygen-rich environment, most of the bacteria in it are aerobic. These bacteria demand a lot of oxygen. When heterotrophic bacteria flourish in the water column and transition to an aerobic condition, the oxygen level of the water is significantly reduced.

The main danger to fish during a bacterial bloom is oxygen starvation, as heterotrophs are harmless to them. During this portion of the nitrogen cycle, fish may be panting for oxygen near the surface of the water, therefore increasing aeration is a good idea!

What causes bacterial blooms? The primary causes are: Overfeeding, dead fish, or dead plant materials will increase heterotrophic reproduction in order to break down organic waste; nevertheless, they proliferate too rapidly to adhere to a surface, resulting in a bacterial bloom.

Because the nitrifiers are sluggish to catch up when ammonia output rises owing to increased mineralization, an ammonia spike develops until the autotrophs multiply sufficiently to handle it. Ammonia spikes are caused by bacterial blooms, not the other way around, contrary to common assumption.

It is unclear whether the autotrophic nitrifiers ever bloom into the water column or if they simply multiply too slowly to cause this effect.

A Last Tip

Severe bacterial blooms are typically avoided with regular partial water changes and proper tank maintenance. The bloom will fade in new tanks as the nitrogen cycle establishes and stabilizes.