Saltwater Aquarium/Algae problem


QUESTION: We have had our tank set up for about two years now.  We added fish in the 6-8 month period along with some corals and maxi carpet anemone.  We have LED lighting with moon and whites.  Everything was great and all of a sudden we started to have this algae growing.  It resembles brown hair algae so we put in 2 sea hares (75 gallon).  They have been there for about two weeks now with no signs of improvement.  Our local store gave us some stuff to put in the tank that was suppose to kill the algae and right after we did that all the fish died!  We took this as a chance to take all the rocks out a scrub them really well and clean everything.  We have since added some urchins and a few more fish including tangs and the Algae is back with a force.  I've been looking and I think that it resembles Dinoflaggelates.  It's like brown shot on all the rocks and has a log of bubbles.  It is also starting to overtake our corals, especially the cabbage leather and it seems as though water changes don't help.  Please help!!!  I'v read to raise nitrates to between 2-3 and leave the lights out for 72 hours but I don't want to lose the corals and fish.  will more urchins help or maybe some algafix???  we are so frustrated, it looked so beautiful. 75 gal tank, 30g sump tank with protein skimmer, phosban, and uv sterilizer.

ANSWER: Hello Terri,

it sounds like you have a nice setup there and really know what your doing! it would help me a bunch if you could tell me what brand of led fixture you have, alot of the less expensive fixtures have good light output, but the light wavelength that they are in often causes excessive algae growth. also one thing that really causes algae to get out of control is lack of flow, in nature algae often grows in areas of little to know flow if you really want to get rid of the algae i would suggest getting a few more water pumps to put in there to increase the overall turnover in the tank, and maybe even point a couple power heads at troublesome algae spots in the tank and hopefully that should get rid of them.

also it would help me if you gave me the exact params of your tank (ph, alkalinity, nitrates, nitrites, phosphates, salinity, etc.) and a list of the corals and livestock you have in the tank. when you said you put "tangs" in the tank thtat suggest you have multiple tangs in the tank, i would suggest fixing this as there are only a few tangs that can live long term in a 75 gallon tank, any need larger tank, and even with smaller tangs that can fit in a tank of that size you can only safely have 1. tangs are larger fish and therefore create more waste than smaller fish, this could put quite a weight on your bioload and cause water quality to drop, which also causes algae to increase growth most the time. i would suggest doing these things before purchasing any more animals to simply eat the algae, as even though you are told they eat the algae, often times that doesnt exactly work out as planned haha.

Hope that helps Terri.


-follow up on this question if you have further information to give me about your tank.

---------- FOLLOW-UP ----------

tank 9-19-2013
tank 9-19-2013  
QUESTION: We have two False Percula Clowns, one Juv. Fox face, One Juv. blue hippo, one Juv. Yellow Tang, two diamond gobbies (thought ours died when he didn't appear for about a month then decided to show himself after we bought a new one), and a Desjardinian (sp?) Sailfin (we thought we were getting the regular sailfin but got this one instead).  Our local store will trade the tangs if/when they outgrow the tank. We kept this same setup from the begining and everything was fine. only instead of the sailfin we had an orange shoulder.  we also had an octo anemone and bubbletip anemone before the crash.  We have all the normal cleaner things like shrimp, crabs, sand sifting starfish and cucumber, and snails.  The corals are Brain, cabbage leather, mushrooms (fussy grass, ricordia, and green), orange sponge, xenia, and candy cane.  I may have missed one but you should be able to see them in the pic I took.  Most of the corals were just added this year so they aren't very spread yet except for the leather.  somehow all the coral that was in the tank survived the crash along with the inverts.

we have two inflows to the tank from the sump along with an additional powerhead.  we are adding another powerhead today as well.  I can't remember what the skimmer is set to but we empty it once a day at half full.  The last test of the tank showed PH at 8.3 (i think), nitrates 0, nitrites 0, phosphates right at 0. My husband normally handles all of that but I know that everything tested in the ideal range with our kit.  I never can remember the specs for the lights I will ask my husband and let you know that.

hello again Terri,

i would suggest trading in the tangs, as even though they are still small they still produce more waste than say a clownfish. 3 juvenile tangs is still overload in a 75 gallon. the yellow tang is probably the best option to keep, the other two will grow QUITE large.

i believe if you continue with water changes once or twice a week, add some more flow, and maybe switch to a led fixture with a better spectrum you may be set and the algae will stop. there are tons of great led fixtures out there these days. although they are a bit pricey.  

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i have about 15 years of experience in the reefing hobby but have been keeping aquariums for about 20, i am up to date on all the latest equipment such as led lighting, dosers, the new tanks available such as the red sea max and i can help you with many creatures that most other people have never even kept before such as sehorses, cephs, and sharks and rays.


15 years in the reefing hobby and it has come to my attention this site needs some more informed experts.


masters degree in marine biology

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