Algae, Nitrate and Phosphate issues!

[TheBirdsNest]

Hey all,

Happy New Year!

I'm really struggling with my tank and wondering if anyone has any advice as I keep seeing conflicting info online...

My tank has been up for 5 months now, its a Reefer 250 with about 230L volume minus rocks.. I've got x6 Blue/Green Chromis, x2 Juvenile Clowns, A cleaner Wrasse and a Royal Garamma. My water parameters look pretty stable but I cannot seem to get rid of this brown algae.. Each morning the glass is covered in in and the its all over the rocks.. Despite cleaning the tank daily with an algae scrubber, it's back the next..

How can I keep this at bay?

My water parameters are:

Temp: 26'C
Salinity: 35 ppt
Ammonia: 0.25 ppm
Nitrite: *0ppm
Nitrate: 10 ppm
Ph: 8.4
Calcium: 410 ppm
Magnesium: 1280 ppm
Alk: 5.3 dKH
Phosphate: 0.0.2 ppm

Now I was previously using API Salt Water Master Test Kit which gave me a Nitrite reading of 0ppm.. Last week I switched to Red Sea Marine Pro Test Kit and this is giving me a reading of 0.2 ppm..

I had a Candy Cane coral die, shortly after adding it to the tanka and the recommendation from my local marine store was to dose Red Sea No3/Po4-X to remove the nitrate and so I did and my Nitrate and Phosphate were sitting at 0ppm for about 2 weeks. I then noticed some of my pulsating Xenia's weren't looking too happy and after research I found that having low Nitrate/Phosphate is actually bad for corals so I bought and dosed both Nitrate and Phosphate to get to the readings above...

I now see that having Phosphate can promote algae growth so I'm a bit lost on what to do next... Do I re-dose No3-Po4-X to reduce Nitrate and Phosphate again??

I know I need to bring up my ALK, is this the problem?

I do a 15% Water change weekly and also dose Red Res Reef Coral Pro supplement 2.5ml a day..

I'm running a Reef Mat 250, x2 Reef Wave 25's and x2 Reef LED 90's at a modified 23K setting to add 30% white light and reduce the time to 6 hours a day in light in hopes to reduce the bloom.

I really want to get rid of this algae but a bit lost on what to do next!!
It also looks like there is some cyano in there too, mainly on the road at at the top of thank on the rear walls etc.

Any advice would be greatly appreciated!

Thanks.

 

[Randy Holmes-Farley]

I don't know about the conflicting part as much as algae can be hard to get rid of and there are lots of partly successful methods around, but you have at least two totally different pests in that picture: green algae (on rocks) and brownish cyanobacteria (on sand and rocks).

Green algae types are often best dealt with by adding herbivores that eat it. Trying to starve out algae (by lowering nitrate and phosphate) can be a losing proposition as corals and other organisms you want can also suffer before you kill the algae. It would not hurt to reduce the phosphate with something like GFO, but I would not assume that a desirable level (say, 0.05 ppm) is going to eliminate either of these pests.

Cyano is often dealt with by reducing organics and increasing flow.

The alk is low and I'd raise to to 7-11 dKH, but the alk level does not contribute to these pests.

 

[Dan_P]

It seems the color of the brown and green growth is very dark. Organisms that can afford to make all that pigment seem to correlate with being well fed. I wouldn’t recommend starving your fish or coral to tweak nitrate and phosphate levels.

As much as we preach these nutrients are important factors for algae growth, they seem to explain only a little of why nuisance organisms grow. I think that is why there are so many recommended solutions that might work. You just never know what you are dealing with.

Chin up. You are likely going through a temporary rough patch. If the system doesn’t show signs of improving in a month, it might have a rather persistent ecology that will need to be dealt with “harshly”.