Reef Discussion

[davek]

Hey guys,
In the last few months I have been getting this brown algae on my backwall and liverock. Ive been scrubbing and scrubbing but it wont go away. No fish, corals (besides my zoas) or inverts are affected.

Ive tried lights out, reducing nitrates, syphoning it off and scrubbing it off. It comes off in strings and matted chunks.

Its not in the substrate, only on surfaces
Ammonia: 0ppm
Nitrites: 0ppm
Nitrates: <5ppm
Phosphates: 0.01ppm
Alk: 8.2 dKH
pH: 8.2
Temp: 25 degrees
Tank Age: 18 months


Here are some photos;

My zoas haven't opened for months... starting to get annoyed
Any ideas what it is and how I can get rid of it?

 

[macca_75]

Hey There.

What brand test kits are you using (goes to accuracy of the kit)?

How much flow do you have (pumps, tank size, approx. amount of LR, etc).

Also, what is the stability of your parameters? Do you have past readings and dates you did them?

What water are you using (NSW or ASW) and how often do you perform water changes?

What do you use for Top off?

Cheers

 

[davek]

Thanks for your reply.

Nitrates - red sea, Phosphates - salifert

I have a single MP40wES in the 195L tank, 30kg of liverock

I did have higher nitrates but that is now under control due to bigger water changes and the addition of a refugium with chaeto

im using ASW with red sea salt, haven't changed this since starting the tank

I use a smart ATO for topoff but use RODI water to draw from

 

[macca_75]

Flow might be marginal (guessing it doesn't run 100% the entire time).

Also, when did you drop your nitrates? Might be a left over from there.

IME if you maintain good water quality over time, the issue will fix itself. Stability is the key.

How much water are you changing per water change and how often are you doing it?

Maybe also worth checking Mg - I note when mine drops patches of Algae get worse.

Cheers

 

[davek]

Thanks Macca, ill check the Mg. I run the MP40 at between 30% and 50% cause its not a big tank... should I bump this up?

I do a 60L waterchange once a week

 

[macca_75]

30% - 50% (40% average). 40% of 12,000 LPH = 4,800 LPH / 200L tank = 24x turn over.

That's not a bad rate (anywhere between 10x and 50x is general rule of thumb depending on Livestock you are keeping) - but the issue is it is coming from a single point or source.

Do you have dead spots (or low flow) where the algae is worst?

If you can turn it up it won't hurt.

 

[davek]

I might bump it up 10% across the board during the day and keep the nightime rates the same.

the back wall is where the algae is the worst... thinking a second pump (MP10) might be the way to go

 

[Sam Parker]

TDS of RODI?

How much do you feed a day?

How long are your lights in each day?

Any changes to your tank in the last two months? (As in equipment, livestock or routine)

Cheers,
Sam

 

[Buddy]

I had algae like this a few months back but my phosphate and nitrate was higher than your readings.
I increased the flow by a fair bit, increased the water changes to 30% per week and syphoned the substrate every water change.
The brown algae was replaced with cyanobacteria and this lasted about 4 months. I just kept up the same routine and it all eventually disappeared.

What is your water change schedule? I got a bit lazy with my water changes over a few months and I think this algae was the result.

 

[davek]

Thanks guys.

Stocking hasn't changed in the last 6 months and I change 25% of my water once a week.

I feed every three days to cut down on the nutrients and I have my lights on 12 hours a day but that's with them ramping up and ramping down. Should I cut this back?

 

[ezza]

Green hair algae. I have it too. I have adjusted my lights to less white more blue, and dose peroxide in the tank. Targeting some of the large pieces in particular.

 

[davek]

thanks ezza I think ill reprogram my lights... might be too much high intensity during the day

 

[Sam Parker]

Could be too much light.. Would be surprised though. Do you have a TDS reading of your RODI?

 

[davek]

Hey Sam, TDS is 0.0.

Ive adjusted lighting back to a natural light (radions) at 85% intensity

 

[Sam Parker]

Hmmmm, I'm at a loss! Params look fine, they have been fine for some time. You use quality RODI to top off and to make ASW, Flow sounds right and you don't feed much. Curious to know if the lights make much difference :/

sam

 

[davek]

Thanks for your help Sam!

 

[Sam Parker]

I guess the effort counts, but I have no suggestions for you!!! I would be curious on mag values and the effect from more flow and less light though

 

[davek]

Oh that reminds me, the Mg values... tested with red sea kit it came out at 1320 with a dKH of 7.7 (ive just dosed this a little bit to bump it up)

 

[Sam Parker]

That's spot on :(

 

[ReeferRob]

How old is the tank? If it's new, the issue more than likely is phosphates leeching from the rock.I'd run a tiny bit of GFO to see if that helps. New rock will leech phosphate for 1 year to 18 months depending on how much is inside of it.