Brown algae that I can't get rid of

[alang_94526]

I have a 7 year old, 134 gallon FO + Liverock tank with RO water, and a brown algae problem that started several months ago that I just can't get rid of.
Phospates, nitrates etc are all negligible levels.
Using LED lighting and cut it down to 3 hours a day at one point with no effect.
I change about 50 gallons of water every 2 weeks. I've tried changing 25 every week but that had no effect either.
I tried turbo snails which don't seem to make a dent on the problem.
Algae starts to be very noticeable within 2-3 days of cleaning tank.
It is very visible on the glass and sand.
Picture attached.
Does anyone have any suggestions on how to curb this?
Thanks,
Alan

 

[Ace25]

Need more info on your filtration, but first thing that comes to mind to help the problem is carbon.

 

[greech]

The growth despite 3 hours of light suggest diatoms. Pic looks like them as well. Are you using RO/DI for your water changes and does that filter have a silicate cartridge on it? Either way, you might consider using Rowaphos in a reactor or HOB power filter (doesn't have to be fancy). If you are running a wet dry or canister, another option is Polyfilter (brand name) pad. Florida fighting conchs will also help with the sanded. I would add at least 6 to a tank your size.

 

[alang_94526]

Thank you both so much for your replies.
Below are answers to your questions.

My filtration is split between the tank which has live rock and live sand, and a 30 gallon sump that has 2 filter bags, a protein skimmer a phosphate reactor with Phosban in it and a bag of carbon.
The water is 100% RO
http://www.bulkreefsupply.com/brs-4...m-75gpd.html?gclid=CN_2v_fZxLsCFY2DQgoddhcAig
I don't think it has a silicate cartridge though I can look into that if you think it would help.

The carbon hasn't been replaced in a long time so maybe I can start with that.
I am assuming the Rowaphos and Phosban are the same so let me know if I have that wrong.

 

[Ace25]

Carbon does not last long at all in a saltwater environment. If you get 7 days out of any carbon you will be lucky. So that is a good cheap place to start.

Rowaphos and Phosban are the same, and both of those normally last 30 days on average.

Silicates are definitely something to look into, that is also a major cause of diatom blooms and old RO filters will allow silicates to get through. If the RO filters are 'up to date' so to speak, silicates should not be an issue. I ran into that problem myself in my early days when I relied on RO dispensers at grocery stores to be maintained, learned the hard way they were not. A Salifert Silicate test kit showed me how bad the source water was and why I was having issues with diatoms.

 

[greech]

I know everyone says that phosban and rowa are the same but in my personal experience, rowa is the only one that finally beat my diatom issue for good.

I do think your source water may be the issue. Might look into a silicate buster cartridge.

 

[Ace25]

I know everyone says that phosban and rowa are the same but in my personal experience, rowa is the only one that finally beat my diatom issue for good.

Here is my issue with Rowaphos (and I did use it myself for over 5 years simply going on faith before I learned better). I was told the same thing when I was buying Rowaphos all the time. It is acid washed, making it somehow better and more able to remove silicates was the line told to me. Truth is, it works the same. Show me some hard evidence to the contrary and I am open to change my mind, but short of that, I have to go off the evidence already published.

http://www.advancedaquarist.com/2004/6/review
http://www.reefkeeping.com/issues/2004-11/rhf/

Rowaphos also claims 'Within the reef aquarium, phosphates will greatly affect the formation of coral skeletons by reducing calcification by over 50% and by inhibiting the deposition of strontium. It is suggested by Borneman that phosphates are a direct poison to calcification.'

This also goes against the current scientific studies that show phosphates actually increase coral growth and no ill effect to calcification up to the .5 phosphate levels.

http://www.advancedaquarist.com/blo...els-increase-growth-rate-in-acropora-muricata
http://reefbuilders.com/2011/12/05/acropora-phosphate-growth/

As for silicate removal, again, works the same and Rowaphos does not make any claims that it works any better for silicate removal than other GFO. One of my biggest issues with Rowaphos is they constantly make claims that "Berlin Technical University showed RowaPhos to be the most effective commercial phosphate remover that they tested", yet, there does not seem to be any study done that I can find by them on that topic, nor does Rowaphos link to the study they reference, which to me falls into 'snake oil salesman 101" tactics. To me it is not acceptable to make claims about a study showing your product was independently tested and your product was the best, but not show us the study, just say 'trust us, it exists'. Sorry, when it comes to science, I don't just 'trust' that someone is telling me the truth, I want to verify it myself, and if they make it hard for me to do that (by not linking to the study), that isn't a good start in making have trust in the product, especially when there are other studies that show it isn't any better, just more expensive.

 

[alang_94526]

I ordered a silicate test kit (neither of my local fish stores have one), some Rowaphos and carbon.
I also bought another 16 turbos so within the next few days I'll have a silicate measurement and I'll at least try, the Rowaphos and Carbon to see if that helps.
If I have silicates, I'll spring for a silicate filter.
Thanks again for the advice.

 

[greech]

I have never tested for silicates but keep in mind that the diatoms are using them. Similar to algae consuming phosphate and nitrates, you may see a low number which could be deceiving. A tank the size and age of yours is bound to build up silicates eventually. Since you are running phosban you should be fine but don't overdose the Rowa. I would also suggest changing it more frequently in the beginning. Probably let the first batch go for no more than 2 weeks.

Completely understood the skepticism Ace. Lots of miracles out there. The rowa worked for me when nothing else did so I'd recommend it.

 

[alang_94526]

My long-awaited Silicate Test Kit arrived and I did 2 tests. 1 on the tank water and the other on newly created RO.
In both cases the silicate level was in the 0-1mg/L range (probably closer to 0 than 1).
My Rowaphos should arrive next week for the second part of the experiment.