Red/Brownish Alge

[Yanir34]

Hello everyone !
I'm in this hobby in the last 15 years , and have rub several tanks.
The current system is 500 liters SPS tank + 120 LPS tank , bothe connected to 210 liters sump .
1 month ago I switched from MH/LED lightning to ATI power module hybrid T5/LED lightning.
Since then I noticed that I don't see any new Coralin alge grow . instead , I see this Red/Brown alge that spread over the rocks and "killing" the purple Coralin alge.
the tanks are 6 month old , and I also have refugium but the Cheato is barley growing.
No3 and Po4 are almost 0 , with icp test.
how can I solve this situation ?

 

[anthonygf]

I don't think the macro algae/cheato will grow without nutrients. I would run the refugium without macro algae for now until your nutrients, NO3 and PO4 are high enough to support them. Take out the cheato for now and see how your nutrient does.

 

[Yanir34]

I also started to dose No3 and Po4 , forgot to mention it.Also I have 5 tangs , 5 anties, 15 blue chromis

 

[anthonygf]

I also started to dose No3 and Po4 , forgot to mention it

The other algae is most likely consuming them. What are your other parameters? Sometimes raising magnesium to 1500 will help slow or stop algae growth. Worked for me, running high mag and seems to loosen the algae's grip on the rocks and makes it easy to remove. Just keep removing it by hand.

 

[Yanir34]

The other algae is most likely consuming them. What are your other parameters? Sometimes raising magnesium to 1500 will help slow or stop algae growth. Worked for me, running high mag and seems to loosen the algae's grip on the rocks and makes it easy to remove. Just keep removing it by hand.

I can't raise the Mag so high , the tank is populated with 15 SPS corals.
here are the parameters, last icp test 3 days ago :

 

[anthonygf]

Well you will just have to work on removing the algae as best you can until you nail down what is causing this problem. I have a branching monti and another sps coral I forget the name has survived the high nitrates for a couple years.

I just now hurt my monti by dosing Dino-X and Reef Flux RX together, I know it was a gamble but I tried everything for several months for my dinos and GHA together. After a couple days the polyps turned white, I did a massive water change and added carbon and a poly-filter. Some of it is still alive.

 

[anthonygf]

As for your lighting I can't help you any but it looks like the algae loves LED's. I am now going to start lowering my magnesium to see where that takes me. I stopped all chemicals because of my sps and I did reduce the dinos and GHA. Well I hope you get this solved. Keep my updated. Off to bed now. Take care.

 

[Yanir34]

Thank you !