How to Control Algae in Saltwater Fish Tanks?

Saltwater Fish Tanks

There are a few problems you might have to deal with as an aquarium owner, and one of them is algae trouble.

Green hair algae, blue-green, red-slime, cyanobacteria (brown diatom), bubble and many other types of algae may decide to share water space with your fish, and it is your job to kick them out.

When you are trying to figure out why you are dealing with algae, there are a few things you need to put into consideration.

The growth of any kind of algae is based on the following factors:

1. The amount of nutrients they have to feed on (DOC’s – Dissolved Organic Compounds).

2. The quality and intensity of light they are exposed to.

3. The number of phosphates and nitrates, and for diatoms, the silicates available for them to feed on.

4. Using an improper make-up or top-off source of water. (Tap water usually contains phosphates, nitrate and other unwanted elements).

5. Using a poor quality sea salt mix that contains nitrates, phosphates or other undesirable elements.

6. Inadequate or poor aquarium maintenance care. This allows excess amounts of phosphates, nitrate and other unwanted elements to accumulate in your fish tank.

7. Low circulation or flow of water in the aquarium.

8. The absence of natural algae eating predator in your aquarium.

The growth and appearance of algae in your aquarium is not a bad thing in itself. In fact, it is the regular order of things and proof that your fish tank is in a healthy state and well balanced.

In other words, the growth of microforms is beneficial to your tank in various ways. The only time algae growth becomes a problem to your aquarium is when you allow them to grow to the point where they cover everything in your fish tank.

We have already listed above, the factors that can cause algae to grow into nuisance proportion in your aquarium.

Now let’s check out the possible ways of eliminating offer reducing them to a safe minimum in your fish tank.

1. You can choose to remove excess amount of algae with your hand, by filtration, or siphoning.

2. Depending on the kind of algae you are dealing with, you may need to adjust your aquarium lighting either higher or lower.

3. Consider the removal of excess nutrient through protein skimming.

4. Reduce phosphate and nitrate

5. Reduce silicates by using the right substrate materials (gravel/sand/live sand). The best option is the aragonite type

6. Make use of DI or RO water for top-off water or make-up water.

7. Use the best quality sea salt mix you can get. (Be careful when choosing carbon also, as this can introduce some unwanted elements as well).

8. Decrease or increase the circulation or water flow in the aquarium, depending on the type of algae you are working with. For example, species in the Cyanobacteria class like red slime algae prefer low current areas, while most hair/filamentous species of algae prefer high current areas.

9. Add natural creatures that feed on algae. Various forms of brown, red, and green algae can serve as browsing food for many types inverts and fish, and many macroalgae species are often cultivated in the fish tank for this purpose. There are a lot of marine creatures that depend on algae as a significant part of their feeding. Surgeonfishes and tangs of the Ctenochaetus & Zabrasoma species and most Angelfishes are typical examples.

10. If your pet fishes can’t keep up with the growth of algae, you can periodically harvest some of the algae to keep it in check without totally eradicating it from your fish tank. Introducing some other herbivores like Hermit Crabs and water snails, as well as some detritivores like Sea Cucumbers, Starfishes and Marine Worms, are all highly beneficial to your aquarium. Just make sure to get the correct types that will feed on the kind of algae you are are trying to reduce in your fish tank.

11. Consider growing some competitive macroalgae. According to Robert Fenner’s article in WetWebMedia Green Algae-The Chlorophyta, he discusses both what he tagged good and pest types of macroalgae. When it comes to the benefit – Algae Control section, the author points out that by making sure to grow an initial batch of algae, you discover it, in turn, can “reduce or prevent” the growth of unwanted pest algae types like hair, slime, bacteria and fungus forms. The logic behind this practice is that all algae compete for the same mount of light, space, and nutrients that is available in a fish tank, the growth of a beneficial type of competitive macroalgae prevents the pest types of algae to grow at all, let alone grow aggressively.

Because when you go to the market in search of chemical additives to help fight the over growth of algae, you will find plenty of them, you might be tempted to opt for them as the more comfortable option for algae removal or control.

However, it is preferable that you go for proper fish tank maintenance as it is key to combating these issues in the healthiest way possible.

With proper fish tank maintenance, algae should not pose a problem to your fish tank or your swimming pals.

If you clean and maintain your fish tank on a regular basis, the only time you will see algae flourish in there is when you miss your routine cleaning.

However, it is evident that might make every person who has a fish tank has the time to engage in the purification of algae on a regular basis, so the option of chemicals is unavoidable in this case.

If you must make use of over the counter remedies, make sure discuss with a good pet store attendant who you are confident is knowledgeable in this area, or you can get in touch with a mail order supplier who can give you quality advise on what product to buy.

There’s a fun fact you might have heard of but never paid attention to; that copper sulphate was used originally to control the growth of algae in ponds and fish tanks.

If was later discovered that the same copper sulphate could help control parasites in fishes.

This explains why when you treat a fish tank that contains only fish with copper sulphate, you will never have to worry about fighting with algae.

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