How To Get Rid of Cyanobacteria (Red Slime Algae)

How to Battle Cyanobacteria.

Cyanobacteria is reddish-brown in color and first appears in an aquarium in small clumps or patches. If not treated, the algae will spread and form a thick ayer across your aquarium. Once present cyanobacteria can be challenging to remove. The common name for cyanobacteria is “red slime” algae. Red slime algae is actually a bacteria and not an algae. Red slime algae needs two things to thrive in an aquarium light and nutrients to grow.

Lightings effect on Cyanobacteria.

Having aquarium lights that are below 10,000k can contribute to the outbreak of cyanobacteria. As metal halide lights get older they loose their intensity and tend to lean towards the red spectrum. Metal halides should be replaced every 9 to 12 months for optimal efficiency.  I can not even being to tell you how many times I heard old metal halides being the cause of cyanobacteria outbreaks.

cyanobacteria outbreak

Nutrients effect on Cyanobacteria.

Dissolved organics cause big problems in saltwater aquariums. They are also the biggest contributing factor to cyanobacteria. Take the phosphates and nitrates out of the marine aquarium and you will starve the cyanobacteria out!

Phosphate (PO 4) is commonly introduced into aquariums by different means. Using unfiltered tap water, an inadequate R/O system or old RO filters as well as dying plant life should be the first places to look at for phosphates. A TDS meter (Total Dissolved Solids) can be used to ensure your R/O system is working properly.

Nitrates are a byproduct product of the nitrogen cycling and also play a part in cyanobacteria outbreaks . Water changes and removing detritus can help with bringing nitrates. If you haven’t noticed a common trend in this article all of the causes of cyanobacteria outbreaks seem to be built around regular aquarium maintenance.

Anything decaying in the aquarium will also contribute to water parameter problems and should be removed quickly. Uncured live rock and  uneaten fish food will contribute to poor water quality as well. A clean up crew is a set of invertebrates put together with one goal in mind, cleaning your saltwater aquarium. Different invertebrates serve different proposes that why it’s very important to have a variety. Hermit crabs are great for eating detritus and uneaten food.

3 Ways to remove Cyanobacteria.

Keep your aquarium lights fresh.

  • Do you replace your bulbs annually? Replacing your light bulbs every 9-12 months can have a huge impact on your aquarium husbandry.  Over time, the light spectrum of bulb can change. This can have a negative impact on your aquarium. Nuisance algae blooms and damage or death to SPS corals. Some Hobbyist write the install date, right on the bulbs with a sharpie as a reminder.

Do weekly water changes.

  • A 10% (of the total volume of the aquarium) water change should be done weekly for the first year of the aquariums life.  This does two thing for the saltwater aquarium. It removes nitrate and phosphate form the aquarium as well as replenishes beneficial nutrients back into the aquarium. After the first year of the aquarium’s life you can start to rely on water parameter testing to indicate when you need to make a water change (keeping nitrate levels below 10 ppm).

Stay on top of your aquarium maintenance.

  • When it comes to aquarium maintenance its hard to generalize information so that is useful for everyone because no two aquariums are the same. If you were to set up two aquariums with the same materials at the same time and both of them could have completely different results as well as maintenance needs. Check out our post on saltwater aquarium maintenance it has a free checklist  download for your aquarium at home.

Cyanobacteria outbreak are a reflection of how good you are doing as a Hobbyist. When it comes to maintaining a saltwater aquarium, many hobbyist can find them selves repeating the same aquarium maintenance they’ve always done. One of the keys to success with saltwater aquariums is constantly improving your ability to care for your aquarium. Aquarium keeping methods and aquarium equipment are constantly changing and improving. To find success, a hobbyist must keep up to date in the latest information regarding aquarium husbandry.

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I just wanted to wrap things up by saying that I’m here for you. I want you to succeed as you begin with your saltwater aquarium efforts. Feel free to contact me. I will do my best to respond to your emails and answer any questions you my have about getting started with  your saltwater aquarium.

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