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FAQs on Marine Algae and Their Control 19

Related Articles: Avoiding Algae Problems in Marine System, Algae Control, Marine Maintenance, Marine Scavengers, Snails, Hermit Crabs, Mithrax/Emerald Green Crabs, Sea Urchins, Blennies, Algae Filters, Ctenochaetus/Bristle Mouth Tangs, Zebrasoma/Sailfin Tangs, Skimmers, Skimmer Selection, Marine Algae, Coralline Algae, Green Algae, Brown Algae, Blue-Green "Algae"/(Cyanobacteria), Diatoms, Brown Algae,

Related FAQs: Marine Algae Control FAQs 1, Marine Algae Control 2, Marine Algae Control 3, Marine Algae Control 4, Marine Algae Control 5, Marine Algae Control 6, Marine Algae Control 7, Marine Algae Control 8, Marine Algae Control 9, Marine Algae Control 10, Marine Algae Control 11, Marine Algae Control 12, Marine Algae Control 13, Marine Algae Control 14, Marine Algae Control 15, SW Algae Control 16, SW Algae Control 17, SW Algae Control 18, SW Algae Control 20, SW Algae Control 21, & Marine Algicide Use, Nutrient Limitation, Marine Algae Eaters, Culturing Macro-Algae; Controlling: BGA/Cyano, Red/Encrusting Algae, Green Algae, Brown/Diatom Algae, Phosphate,

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Marine Aquarium Algae Control

by Robert (Bob) Fenner

Re UV Question... now algae issue 11/15/11- 11/21/11
Hi James,
<Hello Jim>
I am still having problems with algae. I clean my sand and it turns brown a hour later. I thought it was my lights, but its doing it with the lights off.
<Mmm, diatoms or other algae?>
I did a 25% water change yesterday and it did not help. Could it be my water?
<Possibly, may want to get a RO unit.>
I have a 180 reef. Nitrate, ammonia, nitrite are at zero. ph 8.2 Salt Gravity 1.025, Temp bumps fro 79 to 81. The tank is a 180 tall 4ft long 3ft deep. It has two 150 watt 10000k metal halides and two compact 90 watt actinic.
<How is your stocking level, filtrations, etc. Not much to go on here.>
<You're welcome. James (Salty Dog)>
Re Was algae contr., now chatting re reef stocking... NOT other subjects 11/22/11

Hi James,
<Hello Jim>
So as the stocking level goes I have a small adult blue faced Angel ( Who is about to be fish stew because he wont stop nipping at my coral), Emperor Angel, Naso Tang, Yellow Tang, Royal Gramma, two clown fish, three Chromis, and a Long Nosed Hawkfish. I <have> several different types of soft corals, mushrooms, and a Bubble Coral. I know my Angels, and the Naso are going to out grow my tank. I am currently scouting for a 300 gallon dream tank. I have a Octopus skimmer also. I have one more question also. Is there any coral besides mushrooms that has colors and is easy that my angels will not bother? I also went and got some RO. water, and bought a algae that grows in your sump. My lfs guy said it will suck up all the nitrates and algae. I guess I am suppose to turn the light on in my sump every night for it to
survive. I don't do a lot of dealings with my local fish store. Every time I have bought something it always comes with a disease. I do have 55 gallon quarantine tank too!
<The angels and tangs do account for a good amount of waste in your system.
You did not mention water flow, you should have a total flow rate of at least 1800gph. This can help in reducing algae growth. There are many things you can do to reduce algae growth, more than I have the time to say but reading here and implementing will help control nuisance algae growth.
<You're welcome. James (Salty Dog)>
Re UV Question... NOT 11/15/11- 11/21/11- 11/22/11

Hi James,
<Hello Jim>
Ya it seems the Algae problem is under control for now. As far as water flow goes I have two Rio power head 2500, behind my live rock. One is pointing down the other Is pointing across. I also have Hydor Koralia Magnum Pump 5. Pointing towards the top of my tank. I have Maxi-jet 3000 in my sump that is for my UV and its turned way down. I am not sure what size of pump is pushing the water out of my sump, but I it know it flows well. I had one more question. When I upgrade my tank to a 300 gallon, do you think a Blue Throat Trigger would be ok in my system. I read alot <no such word>
about them on wwm, but nobody's really talking reef safe the last few years.
<The Blue Throat Triggerfish is likely the best of all Triggerfish for a reef system but with caution. They likely will nip/attack delicate invertebrates such as Anemone Shrimp. They behave themselves quite well
with other fish and corals but may attack/harass smaller tankmates in smaller systems. Larger tanks seem to have a calming effect on this fish and become well behaved with smaller fish.>
Thanks again,
<You're welcome. James (Salty Dog)>

Help...Please!/Algae/Nitrate Control 10/15/11
<Hello Branden>
I will start out by giving tank specs. to get them out of the way.
<I have read your query and will insert my comments as I go along.>
-55-gallon glass tank
-Aqua C Remora skimmer, it has a Quiet-One 1200 pump.
-216w T5 fixture with two 10,000k and two actinic bulbs
The lights are on from 10:00-8:00
<With your present problem, and having no light requiring invertebrates, I would knock about four hours off your daily photoperiod.>
-Rena XP3 canister filter with only carbon, GFO, and ceramic rings, and I put filter pads on the intake for ease of access, and hopefully helping with nitrates.
<Some brands of carbon can release appreciable amounts of phosphates. I'd replace your carbon with two units of Chemipure Elite which includes GFO.>
-650gph of tank flow not counting the skimmer. I had 825gph but have not replaced the pump yet.
<This should be fine providing there are no dead spots in the system.>
-3 to 5 inches of deep sand bed. The sand is sugar-fine white sand from the beach.
-40lbs of live rock
-ammonia: 0[undetectable]
-nitrite: 0[undetectable]
-nitrate: 20-40
<Yikes. Did you test for phosphates?>
-temperature between 74-77
-use reverse osmosis water for water changes and top offs
-5 gallon weekly water changes
-feed pellet and sometimes a small amount of frozen brine shrimp
<Once thawed, brine shrimp should be rinsed of packing water which does contain waste which
can raise nitrate levels.>
-one Firefish
-one Scarlet shunk <Skunk> Cleaner Shrimp
-five red and blue leg hermit crabs [I know I need more:)]
<Yes, about 20 more.>
-3 narcissus snails
-system is 16 months old
Now on to the problem...problems. I started out dreaming about a beautiful salt water aquarium with coral, fish, and the whole nine yards; so I did all the research I thought could. I asked local fish stores read on the web for several months until I thought I was sound in my knowledge to set up a saltwater tank. I read that live sand was the best and that 3-5 inches was good for nitrate control, so down to Florida I went and brought back a tub of white sand.
<That was your first mistake. Not a good idea to use beach sand, you take the chance of importing unwanted organisms into the system.>
Then proceeded to put this in my newly acquired 55 gallon tank, and my dreams were starting to come true. Found a guy selling his live rock directly from his tank, my tank was cycled within a week. I then started with a Yellow Clown Goby <Please capitalize proper nouns in future queries.> which is a neat little fish. To my surprise Green Star Polyps hitchhiked, in to my tank, but so an enemy HAIR ALGAE [found the id on your site and thus found your site]. The hair algae spread, but my tester strips and my LFS both said nitrates of 20ppm were in
acceptable levels.
<My idea of acceptable levels are 10ppm or lower and test strips merely provide a ballpark figure.>
I now say they were only perfect for the hair algae because it took hold on my tank, and as it took hold the nitrates increased to <too>. About this time I had a Cyano outbreak and "treated" it with ChemiClean Red Slime Cyano remover. After that crises subsided I was able to refocus on the hair algae. I rearranged rocks to a more open aquascape and got the protein skimmer.
<The skimmer should have been installed when you set up the system.>
This seemed to help a little and got the nitrates down some, and the hair algae seemed to grow more slowly.
<Do you clean the combination collection cup/reactor chamber weekly?>
I had also read that lighting could affect algae, and that good light is not liked as much as "bad" light. I then replaced my standard 30w of regular florescent lighting with the above mentioned light.
<A good move.>
Some time between the addition of the skimmer and the light I added an Ocellaris Clown Fish[I forgot to mention adding the firefish and the shrimp.
<Another bad move, you just added another waste producer to the system thereby increasing fuel for algae growth.>
I added them after the Cyano outbreak. At the same time I added the light I had
started feeding frozen brine shrimp because my Clown Goby had a hard time eating the pellets I was feeding. Aware of the nitrates in the brine shrimp feeding happened a little at a time as I watched the fish eat to be sure it was all being eaten.
<As I mentioned above, do rinse the shrimp before feeding. A brine shrimp or fine mesh net works well for this.>
About 3 days after these two changes I noticed a green algae growing in my sand so I did a water change in it subsided a little then with in the week whatever it is got to the intensity it is now. I thought that it would go away with water changes but it only grew. I then was gone for a couple days and while I was gone the Clown Goby died, and my mother is convened <convinced> that the clown killed it because we later saw it chasing and attacking the cleaner shrimp. Since I like the shrimp more the clown had to go.
<And do not add any more livestock until the algae problem is under control.>
Correct me if I'm wrong but I think he got aggressive because he was the "big Dog," and would be better if I had some bigger fish. Do you think I could add a Yellow Tang, and put him back in?
<No more livestock, you do not need to add any more waste to the system.>
Any way I have no idea what this stuff is and I have attached some pictures. I know that 0ppm of nitrates is possible an preferred
<Some nitrates are desired if keeping certain invertebrates such as clams.>
but I can't find where they are coming from! Ever since my tank has been set up there has been little enjoyment because of the headaches, and am at the point to make it better or brake it down.
Oh, and I have something that I hope are brown feather dusters and not Aiptasia. I could not get a picture but these have brown tubes that they draw in to.
<It appears to me that your sand is emitting hydrogen sulphide gas due to excessive waste in the sand bed and is not good. You can verify this by picking up a handful of the sand and smelling it. If it smells like rotten eggs, it's hydrogen sulphide gas. When you change water it is a good idea to use a gravel cleaner type siphon
which will remove some of this waste. Do read here and take action.
Thank You so much.
<You're welcome. When sending photos, do resize to a couple of hundred KB before sending. Large files can quickly fill our server up. James (Salty Dog)>

algae problem, SW... more reading -- 10/07/11
<Lee... where's your grammar; in particular, spaces twixt sentences? Likely the reason your email has been orphaned to date...>
Hi all. Hope you will help me. I'm not a new newbie about 5 years experience in the hobby but I have a real algae problem. The tank that am running at the moment has been running for almost 1 year and I would of thought that it should have ran its cycle by now. Its a jewel <Juwel, a fave brand/maker> 350Ltr corner reef tank. I have good water turn over(10x the recommended)some of it directed across the sand bed(4inch dept).All my stats are at the or as close to natural as I can get none are at lower levels anyway.
<... numbers please; of the values you test for>
My live stock is as follow.14 LPS and SPS corals to fish 3inches in size'2 star fish (sand shifters) 20 or so hermits/snails and about 30 kilos of live rock. My skimmer is a Tm v2 1000 and I have 2 external filters stocked with live rubble, filter floss,bio balls and 1 of them has carbon. I use R/o water for every thing and reef crystals
<Do read here re: http://wetwebmedia.com/aqsysio,rc.htm
and test your salt... some batches of Aq. Sys. product have been trouble. The salt mix alone may be the issue here>
for my salt I change 25Ltr of salt water every week and use about 20Ltr of top up water a week as well. Now the algae only grows on my sand. No where else. Its brown in colour, stringy and clumps together.
<Photo please... this reads like a BGA problem>
I have read about it on your site but I can't remember its name but what I have read about that causes this algae to bloom I have check and rectified in my tank. My lights are the new Tm led tiles(3x 1000 dH tiles and 2 blue reef 600 aquarays)
<Good units>
that I run using the 8 way power controller running the lights at 90% full power for 10 hours a day and 6 inches from the waters surface. I vacuum the sand every week because of this problem can you please help me like I said before tank stats are all good. phos,nitrates ect, ect. <No such word> Do you think its possible that its the light spectrum of the led that favour this type of algae .
<Much more likely the prevailing conditions/set-up, nutrient availability, lack of competitors at work here>
Oh I feed frozen food every other day and liquid food
<Most of these are garbage; feed pest algal et al. undesirables. I'd not use such food/s, and rinse any frozen/defrosted.... ahead of use>
5ml every day. Before this tank I was running the exactly the same set up but with a 250watt 14k ho halide lamp and never had the same fault any help would be great.
Thank You Lee.
<Time to send you back to read. Start here: http://wetwebmedia.com/algaeconMar.htm
and the linked files above... Get back w/ us re testing results, livestock present, whether you have a DSB, DO, Ozone use/RedOx... AFTER you've read. Bob Fenner>

Need help with a "bonsai" aquarium... Pest SW Macrophytes and hydroids 8/31/11
I'm in the process of setting up two Fluval Chi aquariums (a small open topped 5 gallon aquarium with a centrally located "splashdown" filter).
<Am familiar; have written reviews re these systems. Very nice in my estimation>
One is a tiny planted freshwater tank which is causing me zero issues and is designed to have lots of green as the central color with blues, golds, whites and light oranges coming from the fish (a small selection of fancy guppies, neon tetras and a Cory). This tank is irrelevant except to show why I'm setting up my "bonsai" saltwater tank in the color scheme and species selection.
<Ah, I see>
On one side is a plant heavy so mainly green colored, freshwater Chi and on the other is a primarily red colored saltwater Chi with an ominous maroon "volcano" rock play land I created by drilling large and small holes in and gluing "volcano" rocks together and dominated by various red macroalgaes.
During normal days there is a halogen desk lamp set up between the two to act as a light source as the Chi has insufficient lighting for plant and macroalgae growth out of the box and is replaced with a Japanese flower vase when entertaining friends.
<Sounds/reads nice>
My freshwater tank has relatively active and frisky small fish. To showcase the contrast, the only finned friend I'm planning on housing in the marine bonsai tank are dwarf seahorses (Hippocampus zosterae).
Although the freshwater tank has been up and running for five months or thereabouts, I have held off on adding the ponies until I felt the tank had appropriately matured.
I currently have everything I plan on adding except the seahorses up and running but recently found two hitchhikers I find troubling. Currently in the tank I have two species of red sea grape (Botryocladia), two species of red Gracilaria, one Nemastoma and one Dragon's Tongue (Halymenia). For cleanup crew and to complete the "bonsai look", I have a number of Nassarius snails, "dwarf Ceriths" of unknown species and wide color morphs sold from a diver in the Florida Keys that will supposedly stay under a half inch (so far the biggest is a quarter inch), one or more species of Asterina starfish plucked from my coral reef, and some random micro brittle starfish removed from the same.
<Mmm, okay... t'were it mine, I'd simply keep physically trimming (while siphoning) the pest/undesired Macrophytes away. BobF>
Need help with a "bonsai" aquarium 8/31/11
I currently have everything I plan on adding except the seahorses up and running but recently found two hitchhikers I find troubling. Currently in the tank I have two species of red sea grape (Botryocladia), two species of red Gracilaria, one Nemastoma and one Dragon's Tongue (Halymenia). For cleanup crew and to complete the "bonsai look", I have a number of Nassarius snails, "dwarf Ceriths" of unknown species and wide color morphs sold from a diver in the Florida Keys that will supposedly stay under a half inch (so far the biggest is a quarter inch), one or more species of Asterina starfish plucked from my coral reef, and some random micro brittle starfish removed from the same. I also have a large number of Opae Ula/Red Volcano Shrimps (Halocaridina rubra) and massive numbers of pods in all shapes and sizes.
The problem and question is this, everything is fat, healthy and breeding so I feel like in general I'm ready for the dwarf seahorses, BUT I have two very active predatory cnidarians of some sort that hitchhiked their way in despite my best efforts at freshwater dips and quarantine time. I know what you really want is a picture, but I've been unable to take one of either creature that does a decent enough job to be better than the verbal description as they are both small and 99% transparent. I assume they are hydroids but do not let that color your interpretation. Either way, they are very active predators of my pods and it scares me about what could happen once I introduce dwarf seahorses and more importantly their food source of BBS/baby brine shrimp.
The first is almost impossibly long for its tiny size, stretching upwards of maybe five inches at maximum. What it looks like is a tiny (about half the size of a bb shot, maybe a quarter) perfectly round transparent ball with tiny tentacles sparsely decorating its entire circumference connected by an incredibly thin but very long tube to my red sea grapes. It can relatively swiftly retract up and down this thin tube in order to hunt down and capture free-swimming small pods. It's really quite fascinating to watch as the "ball" zips up and down with the relatively quick retracting "tube".
The other concern is a hitchhiker that has no other discernible body parts than a similarly thin whip or rope. It is similarly anchored to the macroalgae but rather than having a ball chasing the pods, it stays mostly retracted and when one gets within striking distance (an inch or two at maximum) it whips out at super quick speed to snag the pod. The first is amazing because it's Cnidarian of some sort (I assume) that is stalking and hunting it's prey, the other is fascinating because it must somehow "see" the pods and get triggered out to seize them at an eye blink.
<Do seem like Hydrozoans, Hydroids>
As the BBS are about the same size as the pods these two bizarre creatures are eating, I'm concerned there might be a population explosion (right now there are about six of the first and four of the second that I've found).
Dwarf Seahorse keepers are terrified of just colonial hydroids and now I have two things 100 times more active in their predation. I'm tempted to use Panacur, but that will definitely kill the dwarf Ceriths and probably lots of other beneficial things in the tank. What is your suggestion?
<Remove the infested rock/s and scrub thoroughly w/ a stiff toothbrush, rinse thoroughly in fresh water...>
Add the dwarves and see what happens? Use the Panacur H-bomb? Reboot the tank entirely?
<Remove the Hydroids first. Oh, and read here: http://wetwebmedia.com/marine/inverts/CnidIndex1.htm
Bob Fenner>
Re: Need help with a "bonsai" aquarium 8/31/11

Thank you very much for the advice!
<Certainly welcome. BobF>

Algae Problem 6/23/11
Hi there Crew, So I have another question for you all. I have a 180 gall tank and I have just put two new 65 watt actinic lights on. I also have two 10,000°K 65W lights. I have been noticing a bluish grayish algae. It looks like little lumps spreading over my live rock pretty quickly. I leave my actinic lights on all day combined with 10,000 k lights. Should I shut the actinic lights off during the day or leave them on?
<I'd start turning them/these off except for "transitional periods, sun up and down for an hour or two>
What causes the algae and is it a bad algae?
<Conditions that permit, favour it... and yes, toxic>
I have attach pictures for you to look at. Thanks, Jim From Idaho
<Likely a Cyanophyte. To be sure requires microscopic examination. Read here: http://wetwebmedia.com/bluegralgae.htm
and the linked files above. Bob Fenner>

Re: Algae Problem 6/24/11
Hi there Mr. Fenner, So I read the article and I know two things I have been doing wrong. 1. I have been adding purple up to increase purple algae. I just threw the bottle away. 2. I have been over feeding. I got a Regal Angel about three weeks ago and he has been eating like a pig and I need to slow down my feedings. Are you saying I should have the actinic lights off after morning and then turn back on for sundown?
<Yes... umm, I'd learn to/use the search tool, indices on WWM. You'd otherwise gain useful insight by reading here: http://wetwebmedia.com/marine/setup/lighting/actinicfaqs.htm
and here: http://wetwebmedia.com/lgttimerstimingfaqs.htm
Do I leave the 10000k lights on during the day, or have everything off all day until the algae goes away?
<Mmm, I would not turn all off if you have purposeful/stocked photosynthetates>
I pulled 10 gallons out and vacuumed the rocks the best I could. Any other suggestions?
<Just what is written, archived on WWM, in books and articles I've penned>
Do you do house calls?
<Mmm, no>
LOL You should come up to North Idaho and see my tank. I read you love Costco, we got one up the road. LOL Thanks again, Jim From Idaho
<Thank you for your kind offer Jim. BobF>

Algae problem, SW, rdg. 5/17/11
Dear Crew
Hi to all and hope all's well there.
A slight problem here and hence am back to my most trusted advisors ( who never seem to go wrong)
I am facing a problem with algae on the rocks and on the back glass.
It seems to reappear on the glass surface the very next day post cleaning.
Not able to get them off the rocks.
Have two turbo snails but it seems to be a too big task form them in this 220 Gallon 6ft oblong tank.
<Mmm, there are other, better approaches. Predation is only one part of a complete control program>
have attached the pictures for better understanding. Please help with the following:
1) What is this algae?
<Can't tell... See WWM re marine algae identification. Need a 'scope really>
2) what is the root cause?
<Can't tell from the information presented. Likely "it's allowed" by your circumstances...>
3) How to get rid of them?
<Read: http://wetwebmedia.com/avoidingalgaeproblesm.htm
and the linked/embedded files and those linked above...>
4) how to keep it from recurring?
<The reading...>
Initially had a hitch that this might due to phosphates/silicates?
<At least in part, yes>
I thought so because the top Up I do is form a normal electric filter ( best available in this country) of course made for human consumption.
I do not own a RO/DI unit and use this source for the top up.
Wanted to be sure before I added some anti phosphate media to the filtration system.
<Measure HPO4 first, and read re on WWM>
Srinivas Manian
<And graphics files of hundreds of Kbytes, not thousands. Bob Fenner>

Algae Problem? SW, rdg. 4/5/11
I am brand new to the hobby and have started a 60 gallon cube tank which contains 75 pounds of Bali alor live rock and at the moment 2 semi-Picasso clown fish. Everything seems to be thriving well, including some bright green algae that is growing up to a foot long in some places. I have looked for similar pictures on your site but have not been able to find anything that looks like it. I don't know if it is good or bad but I would like to know exactly what I am dealing with and how to treat it.
<A myriad of possibilities... likely not "too terribly toxic"... but I'd limit its growth through competition, restriction/removal of nutrients, and likely predation. Please read here:
and the linked files where you find them pertinent, of interest>
I use Ro water and the parameters seem to be in check. Thank you for your time,
Jamie Boyer
Indiana, Pa
<Welcome. Bob Fenner, San Diego, CA>

Water Chemistry and Algae Questions 2/6/11
Hey crew, I had a few questions about water chemistry and algae. In the past I recently had well water for a water source for a coral reef tank. I think the well water is what caused red slime algae to unleash hell on my tank.
I was wondering if using city water has a considerable amount of impact on the amount of algae that will grow?
<Again, possibly Some "well water" is mighty fine, others...>
My other question was that if I stock a tank heavily with photosynthetic corals will they out compete all or any algae for nutrients?
<To some degree, yes. Macro-algae of various sorts can be of even more use... esp. in a RDP sump/refugium setting. Read here: http://www.wetwebmedia.com/algaeconMar.htm and the linked files above...>
I know the coral themselves are not photosynthetic but the algae that grows on/in them is. I will list the parameters of my tank the best of my knowledge since it was quite some time.
46 gallon bow tank
-192 watts of CF lighting with new bulbs (12 hours of actinic and 8 hours or 10000k bulbs, 2 hours of actinic in the morning and at night with 8 hours of actinic and 10000k during the day)
-280 emperor filter with 205 Fluval canister filter with activated carbon, Fluval biological media, and mechanical media (combined flow rate of filtration is 460 gph)
-roughly 300 gph of water flow with 2 powerheads alternating every 15 minutes
-roughly 50 lbs of live rock mostly Caribbean
-roughly 4 inch deep sand bed (aragonite)
-various snails and crabs and one coral banded shrimp
-1 ocellaris clown, 1 blue damsel, 1 scopas tang
-various amounts of mushroom corals, polyps, and a torch coral which I fed liquid coral food
<Ditch this... a major pollutant>
every day about 1 teaspoon of 4 different kinds of food, and occasionally Mysis shrimp (only torch coral got fed, excess food went to other fish and inverts in the tank
-weekly water changes of about 15%
-Kent sea salt and sometimes used instant ocean (but I always wondered how tropic Marin is)
<Fab; superior>
-8.2 pH
-nitrates 0 ppm
-ammonia 0 ppm
-nitrite 0 ppm
-phosphates 0 ppm
-KH and GH where usually low anywhere from 4-6
-all source water was ran through a DI system at a rate of 10gph with activated
carbon and resin and aerated until next water change (minimum aeration time was overnight)
P.S. Any other parameters I might have miss please mention them and I will see if I can recall what they were. As always thank you for your time and advice.
<Keep reading! Bob Fenner>

Salt water Algae problem, 1/16/11
I have a 75 gallon salt water aquarium. It has been two years since start up.
Using live rock . I have a Bak Pak protein skimmer Aquaclear 100 and Koralia power filter.
<The BakPak is underpowered for this sized tank.>
Twenty percent water changes bi-weekly.
<Are you using RO/DI water? What are you phosphate and nitrate readings in the tank and in your water change water?>
Algae that starts out as a purple slime then changes to a green hair like algae is taking over the tank. My
first solution was to purchase Chemi-pure using two units as instructed. I then scrubbed down rock leaving in water so I could not remove all algae from rock.
The algae is winning please advise as what my next move should be.
<Not much to go on here, phosphates and nitrates are the most likely causes. Are you overfeeding?>

SW algal struggle 12/31/10
Hi guys and gals,
<Hello Shelley, I mean Scott!>
I have struggled with algae of one kind or another in my 38-gal reef for what seems like forever. I'm talking almost three years here. I added a Remora skimmer with no improvement. I thickened the sand bed to over 3" with no improvement. I added circulation, until I have 4 300-gal/hr pumps going, with no improvement. I began using RO water since my tap water tested for <10ppm nitrates, again with no improvement. I added a CPR HOB refugium with several pounds of rubble and Chaetomorpha............you guessed it.
<Something present... substrate, hard decor/rock... is a source of too-much nutrient here>
I removed the glass cover and replaced it with egg crate. Finally, the algae settled into a green turf that would come off in large chunks, but no amount of manual removing would get me ahead of the stuff. About a year and a half ago I resorted to vodka dosing with great results, until I apparently overdid it.
The algae morphed into a maroon-colored filamentous algae that is more indestructible than cockroaches. After trying to keep up with this through manual removal, I theorized that what I had was a self-perpetuating problem,
and decided that I would essentially start over. I figured if I could get rid of it as much as possible, my system *had* to be able to keep up with it afterward. I removed all the rocks that didn't have corals attached, and moved them to a lightless saltwater container for several months. So far, so good after putting those back in the tank. However, I still have the algae on my branching corals (frogspawn, torch, candy canes). No matter how often I scrub it off with a toothbrush, I can't get rid of it.
I tried vodka again for a couple of weeks, up to .8ml/day, but wasn't able to arrest the algae, so I stopped. Current stocking is a Royal Gramma, Sixline Wrasse, two Ocellaris, the aforementioned LPS, and a large, bushy leather of some sort. Lighting is a Coralife 2x96w PC, mounted on legs, bulbs were last changed this summer. I do my best to keep dKH in the 9-11 range. Calcium is >400, Magnesium is >1200. Salinity is 1.025, but sneaks up over 1.027 when I'm not right on top of it. In my dreams, there would be a miracle formula that I could dip the branching corals in. More realistically, I would like to try isolating them in another system like I did with the rock, but I don't have a proper light. So, I'm thinking about purchasing a new tank and light which will also serve as an excuse to keep a Peacock Mantis later. So, would a 20H be adequate for the Mantis, or do I want bigger?
<This is a good (enough) size... just need to keep your eye on water quality as the animal grows>
Would a fixture with 2 T5NO bulbs be adequate to isolate the LPS corals, or do I need T5HO?
<The normal output are fine>
If I got the Mantis, I would want to throw a leather or two in to keep things interesting.
<You could>
Thanks for all you do.
<Mmm, and you might look into biological algae eaters:
and the linked files above. Bob Fenner>

String brown algae 11/28/10
Hi WWM crew, I know you guys are busy so thanks for taking the time to answer my questions.
<Welcome Nick>
I am currently battling with a brown stringy algae??, it doesn't really seem to be affecting my live rock or sand, it just seems to end up on my corals.
It is up to 4-6in long and is now causing my coral to close up, I have been blowing it off but it is always back with in hours.
My system is a 130 ltr soft coral tank, 150W metal halide with a 14000K aqua medic bulb, TMC V2 600ltr skimmer, 54x flow and around 15kgs of live rock Nitrates have always been low (<5ppm) and phosphates undetectable
<These may well be being pulled out by the algae>
and I do a 20% water change every week, fish stock is 1 purple firefish along with shrimps snails and crabs.
<Ummm, need more info... please read here:
and the linked files above, where you lead yourself. Bob Fenner>

Salt water algae issues 8/15/10
Hello Experts,
<... "previously married, flow under pressure">
I have a 3.5 year old 155 gallon bow-front tank that has had an algae
problem that I have been working on and just can't find a solution to for the past 2 years. I was told by my local aquarium shop that you are the folks to help me with an answer. I have researched on your website and it seems like I have some flavor of rhodophyta infestation,
<Some of this as well>
although I can't find pictures to match to my particular species. In the past I have tried most of your preventive and control suggestions short of using copper. I really would like to keep the other invertebrates that I have alive! I have limited nutrient input to the point of killing several fish from starvation.
Apparently the algae doesn't provide enough nutrients to sustain to Yellow Tangs/Foxface Tangs/"Meso Tangs".
<Cyanobacteria are unpalatable to Acanthuroid fishes>
I have done frequent water changes of 10% every 2 weeks. I check the nutrient and chemical levels and all that I test for fall in normal ranges, although I admit that my tests are for the key basics, alkalinity, nitrate, nitrite, ammonia, calcium, magnesium, phosphate, pH, and temperature. I have also taken water samples to my local aquarium shop and been told my water is within the normal range.
As I said I have a 155 gallon bow-front, and my lighting is 3 - 150 watt metal-halide lights, 4 - 96 watt actinic blue VHO fluorescents all in a Coralife housing that sits on legs about 6-8 inches above the water. The tank temperature is kept at about 78ºF. I have a protein skimmer in my sump, which has bio-balls for filtration and 25 watt uv sterilizer. I also have 3 circulation power-heads in the tank. Although I can't remember the exact gph rating of all my pumps (sump, circulation, and protein skimmer)
I'm sure they are all well over 500 gph. Currently I have one Tomato Clownfish (Amphiprion frenatus), one "Meso Tang" (actual sp. name unknown), and two Firefish (Nemateleotris magnifica).
I am also including 5 pictures of this plague algae in hopes that you can identify it and suggest a course of action to eliminate this problem.
Pictures 1 and 2 were taken outside of the tank. For pictures 3-5 I broke out my underwater camera to hopefully provide the clearest images I could to help with your analysis.
Thank you so much for your help and I look forward to your suggestions to help solve this problem,
Rob Bronson.
<Read here: http://www.wetwebmedia.com/bluegralgae.htm
and the linked files above. Bob Fenner>

algae... SW, BGA, control, reading 6/23/10
Hi Crew,
Over the years I have come up with a compromise with my hair algae.
<Life is indeed a series of compromises>
I let it grow out in a couple of low flow places and every once and a while trim it. It does at times try to grow in other areas. But I give it a good brushing off and that keeps it at bay for a month or so. I have not figured out why it just does not even try to grow in some places.
<Competition, predation, inopportune circumstances/conditions>
That would be the clue to prevention.
About a year ago I got a coral (lobo) and eventually I could see a blue green colored algae on it that is now spreading all over. It grows long and feathery but it does not come off as easily as hair algae. It feels at if it has roots into the rock. I can brush it down but it always has some left over and grows back rather quickly. I wouldn't mind it except that if it grows on a coral it will smother it. On one section of the lobo it never grows on. On the rest of it it does get very thick. I brush it as much as possible to clean it off but it is back within 2 weeks. I only have Astrea and Stomatella snails and none seem to eat it. Any suggestions besides the standard for reducing algae altogether. My tank is small and I have too many fish to be able to keep the nutrients low enough to discourage any algae. All I need is something that at least feeds on it.
<The usual, reading: http://wetwebmedia.com/avoidingalgaeproblesm.htm
and the linked files above. BobF>

Blue Gargonia <Gorgonian> Suffocating/No Tank Parameters/Useful Information 6/15/10
I have a Blueberry Gargonia <Gorgonian>.
I was told that has an algae growth on it I have cleaned it off pretty well with great success but after 45 hours or so the algae blooms again. Any wisdom would be appreciated
<It's quite obvious that you have excess nutrients in your water fueling this growth.
Read here.
James (Salty Dog)>

New Aquarium 5/12/10
<Hello Jim>
I had a leak in my 55G and have replaced it with same. I also had an extremely bad case of green hair algae in the previous setup. I moved everything, a few pieces of live rock, soft corals, Scopas Tang and 2 Percula Clowns to my 30 gallon sump when the leak started. I have put 40 gallons of fresh saltwater in the new aquarium. My question is, would I be safe in using the live rock in the sump (for cycling) and hopefully not transferring any of the hair algae problems to the new tank? I was really glad for the leak, as I was tired of fighting the algae and this is my main concern.
<There is a chance some algae spores might be released and get into the tank, but growth should be limited as new systems generally do not have excess nutrients causing high nitrate levels to fuel nuisance algae. May want to read/employ suggestions found here and in linked files found in the header. http://www.wetwebmedia.com/algaeconMar.htm >
<You're welcome. James (Salty Dog)>
Jim Nix

Algae and soft coral problems 5/11/10
Hi, my name is Paul. I thought you sounded knowledgeable
<Heeee! Oh, but we are>
so I decided to message you after hitting dead end after dead end elsewhere. First off, my tank and live rock are covered in algae. All kinds, bubble, brown hair, red hair, Cyano, and diatom.
<A plethora! I see the Cyano on your second pic>
None are too bad yet except for brown hair, which is substantially worse than the rest, since my tank is only 2 months old. I have a JBJ 28 with power compact lighting. I also am running the JBJ Nano skimmer
<A feeble product>
in the rear (which in my opinion, doesn't pull out very dark stuff, kind of looks like green tea).
<B I N G O, and bingo was his/it's name oh!>
I started dosing microbacter7 about a week ago with no noticeable change in the tank. I do not use RO water (can't afford).
<... get your own unit if you need this water... for potable et al. uses>
3 days ago I put in a PURA filter pad, which has phosphate remover and carbon in it in the media basket to no avail as of yet. Maybe too soon to tell. Any way to tell if algae is starting to die off?
<Discoloration, dying at the edges, dissolving...>
Have 2 large turbo snails, 2 Ceriths, 7 red leg hermits, and tons of mini brittle stars living in the LR. Now more to my point. I had some Halimeda growing in display very well. After the algae bloomed, it got a short turf of red hair on it in spots. It then stopped growing. A couple of days ago I woke up and it was almost all bleached except for one stalk. Included pics
<Oh, that's what that is>
Also, I have a pink/green clove coral that I got with a coating of diatoms, then they shed off now they grew back as well as some green hair algae. It was doing fine like that until 2 days ago when it closed up except for 2 polyps and now wont open more than 2 polyps during the day. Is it dying?
<Maybe... all chemosynthates (including "corals") need some soluble HPO4, NO3...>
I included pics Param.s are all good, have small frogspawn and red mushroom doing great P.S. any suggestions about my algae problem, other than less feeding, less light, water changes(have tried all) and RO water? Thanks a million! going to kick this algae's arse one way way or another =)
<Oh yeah, oh heck yeah. Read here: http://wetwebmedia.com/avoidingalgaeproblesm.htm and the linked files above and in text where you feel compelled. Bob Fenner>

Will a UV Sterilizer control algae? 5/6/10
Hi crew!
Will a UV Sterilizer control algae?
<A U-V steriliser will reduce, perhaps eliminate, floating algae types such as those that make water green. It will have no impact at all on blanketweed and other types of attached algae. Cheers, Neale.>
Re: Will a UV Sterilizer control algae?
I've got a 240 gallon freshwater tank that I'm still scrubbing brown algae off of the glass every week. Would this help?
Is the brown algae free floating before it attaches to the glass?
Algae is a problem in unbalanced aquaria; better lights, more fast-growing plants, tends to improve things. Cheers, Neale.>

Algae problem 5/4/10
Hi Guys,
Thanks for all your help in the past, you're a great resource.
We've checked through the pages on WWM and also in Bob Fenner's book but we haven't been able to figure out what to do about our algae problem.
We have a 150 litre, reef aquarium. We have a valentini puffer, 2 clowns, a yellow watchman goby and a purple Dottyback. We also have 7 hermit crabs, and some snails. We've had the tank for 2 years. In the tank we've got some xenia's, Zoanthids and leather corals.
We have a powerhead, a protein skimmer and a filter which has polishing pads, rowa phos and carbon in it.
All our readings are good,
ammonia 0
nitrate 0
nitrate 0
phosphate 0
<Mmm, likely the HPO4 is being sucked up by the algae>
Basically all the readings appear to be fine but the problem is that we have a mass of algae growing all over the tank and is proving to be very difficult to control. We have blue-green algae (looks like slimy red
cyanobacteria), bubble algae and lots of green mossy, filamentous algae growing all over the rocks and sand and displacing the xenias.
<Yes, too likely>
Could you tell us how to control this problem? is there an algaecide which we can add to the water which isn't dangerous?
<Unfortunately, no... I'd look into the "usual possibilities" of a DSB, purposeful competing macroalgal culture (in a RDP sump best), the careful use of chemical filtrants... as detailed on WWM>
Also we would prefer not to add any chemicals to the water to control the algae. There is also the additional problem that the puffer traumatises some cleaning crew, like prawns and snails.
I suspect that part of the problem could be due to the puffer insisting on meaty food. We feed him every 2nd day. Is there non meaty food for a puffer that will reduce the amount of waste.
<Unfortunately usually they won't touch much else that is not meaty, messy, but I would try training yours onto Spectrum pelleted foods>
Many thanks for all your help,
<Welcome. Bob Fenner>

Re: Nuisance algae question, SW 4/28/10
Thought you might be interested in how this nuisance algae problem has developed after 3 months, or at least the information might be good for your archives.
After further frustration, my LFS owner recommended a product called Algaefix.
<... the active ingredient is gone over and over on WWM... toxic outright... and the use, even further toxic>
I was reluctant to use a chemical solution, but it did work.
Unlike ethanol, it did not kill the algae. after a few weeks, the apparently healthy hair algae peeled off the rock with ease. A little elbow grease was necessary to get the rest out with a brush, but my aquarium is now basically free of hair algae. There were a few side effects: it killed one particular species of Zoanthid entirely, as well as my Anthelia. All other Zoanthids, corals, and clams were and are fine, as are my fish. So there's that.
What I did learn in this process is that the hair algae was 100% associated with detritus.
<Mmm, maybe these are positively correlated... but not necessarily... i.e. both can exist w/o the other. Conditions that allow/engender detrital accumulation DO encourage algal growth>
Where detritus collected, the algae grew. With my skimmer and running Rowaphos, my nitrate and phosphate levels were completely undetectable. However, I assume there was a lot of both locked up in the detritus that settled on the rock.
<Likely so>
I placed another Tunze stream (Nano) in the lower back corner to blow water through the rock structure. A also
began using filter socks again (rotated out every 3-4 days) on the overflow to my sump, immediately before the skimmer. And I regularly blow detritus off the rock with a turkey baster. This combination seems to do the
I thought I had enough flow with the original Tunze Stream and wavebox but, in retrospect, I think the flaw is the rock structure. If I could go back and do it again, I would build some PVC shelves to elevate the rock and
improve flow.
<Easily enough done with your next re-model!>
<Thank you for sharing Ed. BobF>

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Marine Aquarium Algae Control

by Robert (Bob) Fenner

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