Brown Algae in tank

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Aquarium Advice Apprentice
Mar 29, 2012
Hi have been reading in the forum about brown algae. It is on my glass and some on the sand. Also on my wave maker and the tube the goes up to the trickle filter. I am wondering about this. I have seen on the glass little bit of purple color. Also the brown, and seem to see what looks like string algae which I physically remove. I have a 90 gallon tank and have some crabs hoping they will help. They seem to be some lazy crabs. I have a no RO/Di but plan on getting one, I also have a protein skimmer. On one post regarding this algae issue someone mentioned to remove the filter material from the filter. Is this correct?? My counts are ok, but had a prob with nitrates. It is down to 5. It was alot higher. Been doing weekly water changes about 25% in a 90 gallon tank. All other counts r great. So what can I do, I read it will go away eventually on it's own with the water changes. Don't want to put in a tang yet, as I heard that they will not allow any new fish into the tank after they are introduced. What I have in the tank is the blue green chromies, a trigger fish, a sweet lips (who is a pig, just loves to eat whatever you put into the tank, yes I know he will get big) a Maroon Clown, and an eel that we hardly every see. I had a crab and never see him either. I assume and I can put more fish in a 90 gallon tank, but been waiting for awhile. Oh the tank has been up 2 months about. Thanks for any help. :thanks:
Yes I know the sweet lips will get big. When he does he will be up for adoption. Until that time we will enjoy him. He is a great fish, very active and eats like a pig.
So what about the algae issue. Not sure about putting pictures up, my camera is not working well, and my cell phone not sure how to load the pictures using my cell phone, I will try and post pictures of it thanks

Sounds like diatoms to me.

Your tank is pretty new. 2 months you said.

how long did you cycle it before adding fish?

I had diatoms on my rock and sand in my 800g tank. It's almost completely gone now . I cycled my tank for almost 2 months due to the large water volume and have over 600 lbs of live rock.

I would suggest a clean up crew ( crabs, snails, urchins) .

Go to and read about diatoms and the specific creatures to clean that stuff up.

Post up some pics too that always helps identify the issue!

Good luck
Ya pics would definitely help. I wouldn't add anymore fish to your tank. What type of trigger is it? It probably needs a 125. What is your lighting schedule?
Diatoms are the result of nutrients. You have nitrates what are your phosphates. Also diatoms feed off silicates in the water. If your using tap then that is your first problem that should be addressed. Any kind of filter material in a reef tank is a no no for the most part. It just trapped nutrients instead of removing them which is the job of your skimmer by removing organics before they can break down into nitrates and phosphates. Your second and primary means of removal is water changes with 0 TDS RO/DI.

Trying to fixed a problem without going to the source is never going to get you anywhere.

Nutrient Sources:

You have a nutrient problem, mixed with the fact your tank is new and heavily stocked for a new tank.
Hi thanks for the info. So no filter media in the trickle filter, is that what I read??I am ordering a RO/DI that is for sure and will use that to do water changes. We do not heavily feed the fish, every other day. Only what they can eat and no more. We change the water every week. Our PH and other readings are ok. Just a little nitrates 5 is what it was last week. Doing a water change again. We do have the filter running all the time and a wave maker. Also running is a protein skimmer. I am ordering what they call the clean up crew. So hopefully this will clean up, it isn't that bad. mainly on the glass. A little on the sand by the edge of the glass. Thank you for your help.
Remove the trickle filter completely. All you need is live rock and your skimmer. Other filter types trap organics and completely undermine the skimmers job of actually removing organics. Filters involving any kind of floss or packed media are defeating the point of a skimmer and it is most likely the reason for your nitrates.

Remove the trickle if you have sufficient live rock. Do a big water change and siphon your sandbed removing any debris algae or cyano. After this do weekly 10% changes and your problem will melt away in a few weeks time.

Those trapped nutrients is whats causing your problem.
Wow I have always used a filter in my tanks, of course they where fresh water. I cleaned the filter out, leaving some I guess call it dirt. My tank was getting very dirty looking, water wise. It has cleaned up a lot running the filter. It was off for a few days. Wow you don't need a trickle filter. Amazing. I will do that and will siphon the bottom of the tank. I need to get a new siphon, but I found a few on ebay. Thanks for your help
In freshwater tanks and salt fish only tanks filter medias and floss is not a major issue but in reef tank they cause problems because inverts/corals are more susceptible to nitrates and phosphates. Also the intense lighting in reef tanks can cause algae problems when mixed with nitrates and phosphates.

Eliminating the nitrates and phosphates will starve out algae and allow your tank to flourish under the intense lighting without algae problems.
Pls Vote, yes or no to trickle filter in SW tank thks

Hi all, went to the pet store today. the light they sold me just smoked, so I wanted to replace it. I got a live rock instead. Oh well.
In regards to the filter system they told me not to remove the filter. They said the tank needs to filter. He was against having my tank up without a trickle filter. So seems I get two different stories. Oh well. I will take a vote. So all pls read and vote. thanks
Trickle filter is a biological filter. So is love rock. If you have sufficient live rock then you dont need the trickle.

Ive never had a fish store tell me something useful. And obviously he doesnt know what hes talking about. You can keep the trickle but its not gonna help anything, only hurt. Bet he didnt say why.
Also most reef tanks dont use trickle filters so why would you have to? See where im getting at? Its not doing anything for your system. But obviously choice is yours.
Ok guess no trickle filter. Yes he didn't give my any reason why not to use it. Of course they turned me to the live rocks and not the ones for base rocks. (not live ones) They of course said, who are these people in forums. How do you know they are not trying to grow a certain fish that doesn't need a filter. I had purchased this filter thinking it would help. It sure builds up a lot of yuck, kinda brown looking, well also kinda tan. Anyway so no trickle filter. thanks

No fish needs a trickle filter so that guy is obviously trying to sell crap down your throat. Gotta be careful trusting fish stores. In the end they are looking to make a buck, not so much help.

Forums on the other hand are not trying to sell you anything and have no other motive usually but to help your animals survive and live happy.

Let us know how it goes.
You know you are right. They seemed nice sold me this trickle filter. Can give me no reason why to keep using it. It seems to collect gunk, which I thought was important. I will not use it anymore. Thanks for your advice.
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