Common Aquarium Algae

Today I'm going to address several types of common aquarium algae and how to treat them.


Black Beard Algae (BBA).

BBA can appear in saltwater and freshwater aquariums and starts as black spots that look like dirt on hard surfaces and plants. It normally starts at the tips and edges of leaves and surfaces and works its way inward.  If you try and rub it off with your fingers you will find its slimy and very resistant, that is it doesn't rub off.  

You can get BBA from contaminated plants, ornaments substrate, filters, nets - anything you have placed in or attached to your aquarium; or you can just grow it yourself if you have provided the right environment.

Its commonly thought that BBA is caused by too much light and fluctuations in CO2 levels.  If you do not have sufficient CO2 in your aquarium your plants will be unable to use the available fertilizers and light for photosynthesis, but BBA can and will.

How to kill Black Beard Algae

Seachem Excel is a carbon based aquarium fertilizer that BBA hates.  Dose your aquarium as per the directions and increase the dose gradually every three days until you have doubled the dose.

This will treat your aquarium, however it is also recommended that you remove affected items (including plants) from your tank and soak them in a ten percent bleach solution for 3 minutes.  Rinse under running water before returning to the aquarium.  Pipes filters and all tools should also be cleaned in the same manner.


Blue Green Algae (BGA)

BGA isn't actually algae, it is cyanobacteria.  Some people call it slime algae because of its very slimy feel.  It generally appears as a blue green coat on plants ornaments or substrate and has a strong pungent earthy smell.  Is it appears in full force it can be a foamy mess on top of the water,

Difficult to identify when it first appears as it will camouflage on you plants as little green dots, you most likely first see it on ornaments rocks or substrate where there is enough light to see it.

BGA requires a high level of dissolved waste, particularly phosphates, which can be the result of overfeeding, irregular water changes or poor tank maintenance.

How to kill Blue Green Algae

Physically clean out as much of the BGA as you can.  Vacuum your substrate, scrub down everything!  Change 20% of the tank water and keep all light out of the tank for 3 days.  After 3 days change out 20% of the tank water again. Repeat if required.

Your goal is to seriously improve your water quality and remove dissolved solids from your water.  A TDS meter shown below will help you measure the dissolved solids in your tank and check your progress.




Brown Diatoms Algae (BDA)

Very common in a new aquarium, BDA grows when light is insufficient and there is silica present in the water.  Diatoms require silica to grow.  If you use tap water in your aquarium, this could possibly be the source.

BDA will easily wipe pf surfaces and does not clump like cyanobacteria.  A good wipe down and gravel vacuum is generally sufficient to remove this algae.

If you really need to remove silica from your water, a good product is RowaPhos.  It also removes phosphates. There are other methods to remove silica from water like lime softening, ion exchange, ultrafiltration and alike, but they are very cost prohibitive.

A good starting point however is to ensure you use a quality water conditioner if you are using tap water and increase your lighting to at least 8 hours per day.  Use PondMax CleanMax weekly to eliminate any new spores.

Another thing to do is increase water flow to the effected area of the tank. Perhaps add a submersible filter.


 Green Hair Algae (GHA)

This stuff is usually pretty harmless but you really don't want it in your tank.  The biggest danger of this algae is that it will compete with other plants for nutrient and light to photosynthesize.

Direct sunlight is a sure fire way to encourage this algae.  If your tank is overstocked or there is excessive food, these may also be contributing factors in the growth of GHA.  The excess food becomes waste and eventually ends up as phosphate and nitrate in your aquarium.  Yum yum algae food.

This algae can be easily removed by hand with scrapers and tools.  If necessary you can dip your ornaments etc in a 10% bleach solution for 3 minutes, rinse and return to the aquarium.

Prevention however is all about ensuring you have the right conditions as far as light and nutrient availability.

A great algaecide product which wont damage your nitrate cycle is PondMax CleanMax  Its brilliant for cloudy green water which turn into GHA.




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