Causes and Solutions for Red Slime Algae in Saltwater (Natural Sea water, NSW) Aquariums

Causes and Solutions for Red Slime Algae in Saltwater (Natural Sea water, NSW) Aquariums

Despite its name, red slime algae is not algae but a type of bacteria called cyanobacteria. In addition to being among the earliest forms of life on earth, cyanobacteria are the evolutionary link between bacteria and algae. Scientists think that if it weren’t for these microbes, the sky would never be blue. They produce oxygen as a byproduct of photosynthesis.

Algae growth in saltwater (natural sea water, seawater, NSW)  aquariums poses a threat to the health of plants and animals, and it should be controlled to keep aquariums in a healthy state.

Red slime algae identification

One of the most common names for cyanobacteria is blue-green algae. However, only a portion of these organisms is blue-green. There is a wide range of colors found in saltwater (natural sea water, seawater, NSW), including

• Deep purple to entirely black
• Orange-yellow to reddish-brown
• Blackish green to blue-green

This red slime algae begins as small patches that can rapidly spread to form a mat covering a large area.

Causes and Solutions for Red Slime Algae

Algae that grow excessively are usually caused by conditions like high lighting and/or nutrient levels. In order to grow, algae need these two things. When you try a remedy, you should go through each step one by one. Then there will be no way to determine where the problem originated and which solution worked to fix it once it subsides. See what results in you get by starting with one solution. Continue to try other solutions until the problem has been resolved.

Lighting

All sorts of algae problems are caused by improper bulbs, inadequate maintenance, and excessive lighting hours. In addition to their efficiency at wavelengths between 665 and 680 nanometers (nm), these organisms are active indoors and outdoors between 560 and 620 nm.

Solutions:

• Increasing the intensity and optimizing the spectral quality of the aquarium light can be done by using different types of bulbs, particularly when it comes to full-spectrum lights or color-enhancing tubes.
• The lights should be on between 8 and 9 hours a day, depending on your saltwater (natural sea water, seawater, NSW) tank’s needs.
• Be sure that the bulbs you use are designed for aquarium use, with the appropriate wattage.

Nutrients

For red algae and other slime algae, phosphates (PO4) and nitrates (NO3) are the primary nutrients they consume. A common source of phosphorous in saltwater (natural sea water, seawater, NSW) aquariums is unfiltered fresh tap water and things like foods, activated carbon, sea salt mixes, KH buffers, and many other aquarium products that may contain higher-than-normal levels of PO4. Over time, using Kalkwasser for established reef tanks can precipitate out phosphates, which settle in the substrate and on the live rocks.

Solutions:

• Apply a high-quality salt mix, and RO/DI filtered make-up water.
• Other commonly used aquarium products might contain elements you should be aware of.

Dissolved Organic Compounds (DOCs)

An saltwater (natural sea water, seawater, NSW) aquarium with excess DOCs develops nitrate (NO3) problems. Nitrogen cycling produces nitrates, which can naturally build up to high levels due to the lack of proper aquarium maintenance. This is similar to the way phosphates are introduced.  

Solutions: 

• Maintain good saltwater (natural sea water, seawater, NSW) aquarium maintenance by keeping the substrate clean, keeping the feedings down, rinsing regularly, refreshing or replacing filtering or absorbing materials (sponges, bio wheels, floss, cartridges, carbon) performing regular partial water changes.
• Install a protein skimmer.
• Filters that can be used wet or dry can be used on systems that have been running for several months. Especially bio balls, which contain a lot of bio media, are the natural source of nitrates; they should be rinsing and cleaning regularly.
• Be sure to cure live rock properly before adding it.
• If you’d like to add algae-eating hermit crabs or shrimps to the tank, choose Left-handed or Dwarf Zebra Hermit Crabs, or shrimps, or other good substrate-sifting fish such as orange-spotted sleeper gobies.
• While the saltwater (natural sea water, seawater, NSW) tank is still cycling, avoid adding new animals. Until the tank has finished cycling, avoid any water changes and any primary substrate or filter cleaning tasks, except for replacing dirty pre-filter materials or quickly siphoning anything off the bottom. It’s easy to remove red slime algae, as it’s not very attached to the water’s surface, by either siphoning light water off or using a net or turkey baster to remove floating chunks.

Carbon Dioxide (CO2)

In an saltwater (natural sea water, seawater, NSW) aquarium with little water flow, algae consume carbon dioxide (CO2).

Solutions:

• Consider installing a few powerheads, a surge device, or increasing the flow rate or efficiency of the filtration system, depending on the size of the saltwater (natural sea water, seawater, NSW) aquarium.

Using Additives to Fight Red Slime Algae

Even though cleaning up the tank and following proper maintenance routines will not result in instant results, you can utilize one of the different additives to fix the issue quickly within a few days. There are, however, a few treatments that are effective in only treating the symptoms of the slime algae rather than treating the underlying cause(s) that cause the algae growth.

Since cyanobacteria are bacteria, many of the additives used today have antibiotic properties, weakening or destroying a biological filter base. These treatments should be used with caution!

Testing Can Be Deceiving

Aquarists often see regular nitrate readings because slime algae consume nitrates. Don’t let yourself be deceived. You would probably see a rise in the aquarium’s nitrate levels if you removed the algae temporarily before implementing other solutions. The nitrates underneath the undetectable algae give the impression that they have been kept in check. Other forms of algae also fall into this category.