How do you get rid of green algae in a salt water aquarium?

Question

I have a 65 gallon salt water aquarium that keeps getting that awful green algae on the rocks & bottom of the tank. I have cut down the time that the light is on, bought more snails & that still hasn't helped.

Answer 1

Add natural algae eating critters. Various forms of green, brown and red algae can provide browsing food for many types fish and inverts, and many macroalgae species are actually cultivated in the aquarium for this purpose. There are a lot of marine inhabitants that depend on algae as a major part of their diets. Tangs and Surgeonfishes of the Zebrasoma & Ctenochaetus species, and most Angelfishes are prime examples.
If your fish friends can't keep up with the algae growth, you can periodically harvest it to keep it in check without completely eradicating it from your system. Introducing additional herbivores like Snails and Hermit Crabs, as well as detritivores like Starfishes, Cucumbers and Marine Worms are all greatly beneficial. Just be sure to get the correct types that will eat the kind of algae you are dealing with.
Grow some competitive macroalgae. In Robert Fenner's (author of The Conscientious Marine Aquarist) WetWebMedia Green Algae-The Chlorophyta article he discusses both good and pest types of macroalgae. Under the Benefits - Algae Control section he points out that by growing an initial batch of algae, this in turn can "limit" the growth of unwanted pests types like slime, hair, fungus and bacteria forms. Because all algae compete for the same light, nutrients and space that is available in an aquarium, the growth of a good type of competitive macroalgae deprives the pest types of these elements to grow aggressively.

Answer 2

You don't have to have the filter "out", you only have to have the charcoal or carbon removed so it doesn't remove the medication. Carbon is notorious for removing any medication from a hospital tank. The green water is not a problem for the fish, in fact, they are probably more comfortable in it than crystal clear water. However, it shows that you probably have high nitrates in that tank. Nitrates are what the algae, and all plants, use to grow. The best way to get rid of the nitrates is by doing regular (weekly) partial (25-30%) water changes in any aquarium. Do your water change before redosing with the MelaFix. Nitrates are the end result of decomposing food and fish waste. Ammonia and nitrites are the first two. Cut back on the feeding to once a day and only what they will eat in 5 minutes. Remove anything that is left over. This will go a long way toward fighting the algae. Less light will hinder its' growth also. Live plants will also successfully compete with the algae for any nutrients in the water. All three of these chemicals, when not removed by water changes, will cause a great deal of stress for your fish and hinder their tissue regrowth and their immune system. With damaged tissue, parasites and diseases will try to gain entry to the fish's body. A healthy immune system will fight them off. BTW, bleach is what you use to totally kill off anything in a tank and sterilize it after having a disease run through it. Adding Clorox would be a murderous thing to do to sick or damaged fish. That is just a stupid, mean spirited thing to tell someone to do.

Answer 3

This Site Might Help You.

RE:
How do you get rid of green algae in a salt water aquarium?
I have a 65 gallon salt water aquarium that keeps getting that awful green algae on the rocks & bottom of the tank. I have cut down the time that the light is on, bought more snails & that still hasn't helped.

Answer 4

First, you should be certain that what you're dealing with in your tank is green algae, not a green cyanobacteria - see photo for comparison: http://www.aquamax.de/Shop/Artikelbilder/Zusatzbilder/Algen%20im%20Aquarium_Blaualgen%20-%20Cyanobacteria_STUG_cyano1.jpg

Cyanobacteria isn't an algae, but a BACTERIA! A more common type of this in a saltwater tank is the "red slime" - also a bacteria. Because these are bacteria, not an algae (although they were once called blue-green algae for their appearance, this is no longer correct), traditional algae remedies don't always work to remove them. Chemical means should be avoided, because these will disrupt your beneficial bacteria as well, leaving you to have to cycle your tank again and your tank inhabitants in higher ammonia/nitrite levels while the bacteria repopulate. Here's a Bob Fenner article for control of the cyano, in case that's what you have in your tank: http://www.wetwebmedia.com/bluegralgae.htm

In the event you have a true algae, it helps to know speciffically what critters will eat it - not all like the same things! It may be a bit tedious, but this link is to an algae identification guide with photos - if you can identify the algae, Use the number next to the name to find a corresponding fish or invert that will eat that algae type: http://saltcorner.com/sections/guest/algaepage/algaepage.htm

Since both algae and cyanobacteria need nutrients to grow, try more frequent water changes, and possibly use a phosphate pad to adsorb phosphates in your tank as well as the other control measures.

Answer 5

This Site Might Help You.

RE:
How do you get rid of green algae in a salt water aquarium?
I have a 65 gallon salt water aquarium that keeps getting that awful green algae on the rocks & bottom of the tank. I have cut down the time that the light is on, bought more snails & that still hasn't helped.

Answer 6

I agree with the other 2 posts I have a 60gal tank that had the same problem. I increased the number of blue hermit crabs and I have a much smaller algae problem. I use an aquarium vacuum to get the green and red algae that occasionally starts to develop in the sand

Answer 7

Saltwater Algae

Answer 8

Try adding about 30 small blue leg hermit crabs, 1 or 2 emerald crabs, Red sea star...they graze all day on different algae.
Depending on the fish that you already have, You MAY be able to add a Tang, they love grazing on green algae.
If your tap water is anything like mine, There is lots of phosphates in it so I do topups and partial water changes with RO/DI water.

Answer 9

Agae lives off three things. Nitrates, phosphates, and light. Starving it of its nutrients is the best way to control it. If you are using tap water it is loaded with nitrates and phosphates. Yes federal regulations limit those but test yours yourself sometime and you will notice they aren't always within the allowed limits.

Use only DI/RO/distilled water for saltwater. This will ensure you do not add in any nitrates or phosphates to your tank. Change your water often enough to stay less than 10 ppm nitrates and 0 phosphate. Personnally I think 10% weekly is plenty to accomplish this unless you have a a very high bioload in your tank.

Use your daylight lighting a maximum of 8 hrs per day and your actinics a max of 10 hrs per day. Nothing in your tank besides algae needs more than this. If you only have 1 light source 10hrs is more than enough for your tank. If you have corals I assume you know their lighting needs and will stick to those.

Phosphate removing pads and media will help but unless you remove the source of the phosphates you must continue that treatment. The pure water for water changes will take care of that problem much cheaper.

If you have a sump you can add in a small cheap light and grow various macro algae(seaweed) in it which works as a nitrate removal system. Another alternative is to use a macro algae in the tank itself. I gorw some very nice red macroalgae that I use in my tanks not only for nitrate absorbtion but also for decoration.

If you have live rock the coralline will compete with the algae for nutrients as well. Adding one small piece of live rock will seed the coralline algae to grow. Once it takes over you have some very nice purple and red encrusting coralline instead of unsightly green and brown hairy junk.

The snails and crabs are very important to your filtration of a saltywater tank but not the best for algae removal. Taking out the source of the algae is the best option. If you have a few snails, crabs and some live rock combined with using only pure water for water changes you will have a very maintenance free tank. Everything else will work for you in keeping it clean.

Answer 10

do a water change every 20 days about 30 percent that solved my problem