QuestionQUESTION: I have a newly set up reef tank, just finished cycling, a green algae has formed
coating the glass tops of the 134 lbs. of live rock and staining the water to cloudiness. The tank is a 75 gallon, of which I did a water change of 15 gallons
and it didn't do much to clear the tank. I have moderate to high light. Live sand
and few cleaner crews with a lot more ordered.
ANSWER: Hi Douglas. Have you checked your phosphate level? Did you use reverse osmosis or distilled water when setting up or doing partial water changes? Do you have a protein skimmer and what kind of filtration do you have? For me to answer this question accurately I would have to know what your water tests at and what kind of filtration you have. Do you have any power heads or a strong current?
Is the algae like a hair algae or more of a slime algae?
Most algae need very few things to grow and become a problem in a tank. Light, dissolved wastes in the form of nitrate and phosphate, low current or stagnant areas, and lack of herbivores. Wishing to solve a particular algae problem you often have to seek the cause of it. The cure for a nuisance algae dose not involve a single fix, but many small ones instead, and a bloom may take time to subside after corrective action has been taken. Steering a living biological system in the direction you want it to go is a different matter from controlling algae in one's swimming pool with a measure of chlorine. That said most algae problems arise from the water quality. If you could get back to me with all the specs of your tank I would be glad to further assist you in this matter.
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QUESTION: The phosphate level was at .04 as of yesterday, I used ro water for entire set
and all water changes. I have a very good skimmer and a canister filter and
recommended power heads, am also using a hand on filter trying ti reduce the
algae bloom with the additional filter. The algae is bright green and very fine
and free floating as well. This is a brand new set up.
AnswerHello again. What is your nitrate reading at? High nitrate levels will also allow an algae bloom to erupt in your tank. Is the water tinted green or is it more of a milky kind of cloudiness? It is very common in a new tank to go through several stages of different algae blooms. First you will get a diatom bloom characterized by a light dusting of what appears to be a rusty colored algae. After that clears up it is common to get a bloom of cyanobacteria. Once under control the next algae to typically rear its ugly head is the light green hair algae known as Bryopsis. This will usually be seen on the glass but can cover the rocks as well in severe cases. If left go it will eventually get the fine filaments you usually associate with hair algae but when first growing it appears as a slime-like green growth on the glass. The hair algae seem to bloom in tanks with a slight reading for ammonia and nitrite. If your tank is still in its cycling process this may be why you are seeing this algae. Other factors that contribute to the growth of unwanted algae are high nitrates and high dissolved organic material, as well as phosphate, lighting in the wrong spectrum, and high amounts of trace elements like iron, manganese, molybdenum, cobalt and zinc. If you are adding any trace minerals into your tank stop for a while to reduce the amounts. This bloom you are having may just be part of your tanks personality and one of the algae blooms it goes through as a newly set up aquarium. Some methods for controlling algae are:
Good biological filtration; some algae prefer the ammonia and nitrite that is in a newly set up system. Once these levels drop when the cycling process is finished these algae will subside on their own giving way to the algae that prefer nitrate as a food source. Removing the build up of nitrate by denitrifying filters or frequent partial water changes helps prevent excessive growth of these algae.
Algal filtration; using various forms of algae in a refugium or sump allows a specified space for the algae to grow and these algae take up the nutrients in your water making less algae grow in your tank. You can also have a small spot in your tank where you allow some species of algae to grow to help prevent them from growing on other parts of your tank.
Using caulerpa or other macro algae in your tank; This will do the same as mentioned above.
Using purified tap water; this you already do and I am sure you understand why so i won't go into great detail about this.
Activated carbon; Activated carbon is used for removing dissolved organic substances in your water along with trace elements that may be in your water. It is important that activated carbon be of high quality and replaced every four weeks for maximum effectiveness.
UV sterilizers; UV sterilizers will not remove the algae from your tank but will kill the floating spores and filaments in the water.
Protein skimming; Already employed in your tank, make sure it is collecting a thick green to brownish somewhat smelly liquid. If it is thin and you are able to see through it then the skimmer is not working efficiently and needs to be adjusted down.
Good water circulation; This simply prevents the build up of debris in areas of your tank that will help feed the algae like a fertilizer.
Manual removal; pretty self explanatory!
Water quality; Keeping your ammonia at zero, your nitrite at zero, your nitrate at zero if possible and phosphates at zero will limit the growth of algae greatly since there will be no food for it to thrive off of.
Chances are that even if you employ all the different methods for controlling algae there may still be some in your tank. Right now, since your tank is newly set up, your tank has very little stability. This unstable environment may be adding to the bloom. As long as all your levels are right where they should be, your lighting is of the right spectrum and you have good filtration and skimming the algae will most likely clear up on its own. I never recommend any kind off additive to eliminate algae growth. Most of these not only do not work but also leave the algae a little more resistant to it the next time it appears. And it will, when you are using these chemicals because you are killing the algae but not fixing the problem that caused the algae in the first place. It may take several weeks to a month to get this algae under control. The problem with your water is that it is simply a new tank that is unstable. Give it a little while keeping up on your water quality with testing and correcting any problems that arise. Add more of a clean up crew to your tank and keep up on your partial water changes. Over time this bloom will subside with good water quality and good maintenance practices. You will see! If you haven't noticed I probably mentioned water quality way too many times. That is because with the proper water chemistry algae will not grow. There is a balance that needs to be established in your tank and that balance is not there yet.