Algae – Staghorn & Brown(Diatoms)

At the last GWAPA meeting, I gave a presentation called Algae in the Planted Aquarium. While preparing for the presentation, I had to gather a lot of information from a number of different sources on the Internet. I’ve decided to declare this week Algae Week, and share that gathered information by posting about two types of algae each day. This is the third installment featuring Brown (Diatoms) and Staghorn Algae.

Staghorn (Compsopogon sp.)

Staghorn algae is aptly named as its branching resembles the antlers of a stag’s horns. They are coarse, branching strands that commonly attach to plant leaves and equipment. The strands can appear white, grey, or green in coloration.

Causes:

• Nutrient Imbalance – Strive for the following nutrient levels: N (10-20ppm), P (0.5-2ppm), K (10-20ppm), Ca (10-30ppm), Mg (2-5ppm), Fe (.1ppm).
• Low CO2 – Strive for 20-30ppm concentration of CO2, as permitted by fauna.

Cures:

• Manual removal – Use toothbrush to remove as much as possible.
• Water change – Maintain weekly/bi-weekly water change schedule.
• Increase CO2 – This will stimulate plant growth, which should help the plants out-compete the algae for resources.
• Bleach treatment – Dip affected items/hardy plants into a bleach/water solution using a 1:20 ratio of bleach to water. Before putting them back into the tank, make sure the item is free of any bleach odor.
• Maintain proper macro (NPK) dosing scheme

Note:

• Most fish/inverts will not eat staghorn algae.

Brown Algae (Diatoms)

Brown Algae, or diatoms, often present themselves as a brown, muddy, muck that covers plant leaves and hardscape items. It is rare to be seen in a fully established aquarium.

Causes:

• Newly setup tank – Aquariums that have just been setup seem to be prone to diatom algae.
• Excess nutrients – Silica in particular appears to be a trigger. Contact your water utility company for a report detailing silica concentrations in your water supply.
• Possibly old bulbs – Sometimes, old bulbs can encourage the conditions for diatom algae.

Cure:

• Time – Allow it to use up the excess silica, and it will often disappear on its own.
• Manual removal – Siphon/scrape diatoms manually for quick removal.
• Algae Crew – Otocinclus and Nerite snails are fantastic at clearing a tank of diatoms. They help with other sorts of algae as well.

Sources:

Aquatic Plant Central – Algae Finder
AquaticScape