How often can you blackout for GHA?

Deltec

KonradTO

Well-Known Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 11, 2021
Messages
690
Reaction score
335
Review score
+0 /0 /-0
Location
Germany
Hi all,
For my gha problem I added a fuge, did ICP test, added cuc, etc but it seems that even the smallest mistake (e.g feed too much for one day) fuels them stronger than before.
The only thing that kills most of them until now was doing a 3 days blackout. It does not kill all of them but most.
What if I do monthly blackouts? Or even more often? Would coral be ok with that?
 
Top Shelf Aquatics

Chrisv.

Valuable Member
Review score
+0 /0 /-0
View Badges
Joined
Mar 17, 2012
Messages
2,335
Reaction score
2,577
Review score
+0 /0 /-0
Location
United States
Hi all,
For my gha problem I added a fuge, did ICP test, added cuc, etc but it seems that even the smallest mistake (e.g feed too much for one day) fuels them stronger than before.
The only thing that kills most of them until now was doing a 3 days blackout. It does not kill all of them but most.
What if I do monthly blackouts? Or even more often? Would coral be ok with that?
I think there are underlying issues here that should be addressed. Three day blackout is doable, but it's a bandaid at best and tolerable for coral but certainly should not be a part of a planned routine.
 
OP
KonradTO

KonradTO

Well-Known Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 11, 2021
Messages
690
Reaction score
335
Review score
+0 /0 /-0
Location
Germany
Can you tell us more about the tank? Size, filtration, stocking list, testing results (and kitS used). What you feed and how much.
Sure.
32g, skimmerless with sump-fuge full of macros
Started last august with a mix of LR and dry rock
4 small fish (sixline, bicolor blenny, ywg, chromis)
Cuc: 4 nassa, 4 cerith, 5 bumblebee, 2 trochus, tuxedo urchin, emerald crab. No mexican turbo, they die.
my params: https://www.reef2reef.com/threads/a...-deaths-and-tons-of-gha.907266/#post-10145034
in general are quite stable, NO3 undetectable, PO4 0.03-0.04.
I feed some days pellet food, some days frozen (homemade or mysis) and 2-3 days/week I started recently to dose powder food for corals and bottled phyto (seachem).
I had GHA for 5 months now, the only thing that kills it is blackouts, so if it does not hurt corals, I will just pretend that there is a storm every now and then and blackout + brush from time to time.

edit. for kits I use hanna checker URL and SERA for NO3.
edit2. I also have 4 hermits in the dt and 2 in the fuge
 
Last edited:
Click to join now!
OP
KonradTO

KonradTO

Well-Known Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 11, 2021
Messages
690
Reaction score
335
Review score
+0 /0 /-0
Location
Germany
blackouts dont work, I would suggest to consider other methods
well until now it was the thing that worked the best, it make it almost disappear for a week, than it comes back within another couple of weeks. It could work if I can do it every 2-3 weeks I guess.. And while my DT is in blackout I still run the fuge so nutrients can be displaced there. The question is how much does it hurts corals if I do it more often..
 
OP
KonradTO

KonradTO

Well-Known Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 11, 2021
Messages
690
Reaction score
335
Review score
+0 /0 /-0
Location
Germany
When you do the blackout and the gha goes away, do you ever notice a bump in your nutrients?
No last time I checked right after the blackout I had 0 nitrates and 0.04 po4 ...my macros probably get rid of them quickly. Also I recently added a ball of chaeto (2 weeks ago) and it doubled in size already. My guess is that nutrients are there but get depleted by macros and gha quickly. The problem is that is almost impossible to brush all the rocks with GHA, and in some cases I have palys so I do not dare to brush those.
That's why I am considering to use monthly/bimontly blackouts.
20220514_191051.jpg


20220514_191036.jpg
20220514_191047.jpg
 
OP
KonradTO

KonradTO

Well-Known Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 11, 2021
Messages
690
Reaction score
335
Review score
+0 /0 /-0
Location
Germany
Don't mind at the bubbles, are not produced by the algae (it does not look dino to me). When I clean I bubble scrub the tank for sending all the particles to the filter.
 
REEFTIDE
OP
KonradTO

KonradTO

Well-Known Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 11, 2021
Messages
690
Reaction score
335
Review score
+0 /0 /-0
Location
Germany
How about manual removal?
Yes I am doing it weekly but some spots are simply too impractical to reach and shortly after I "graze" them they grow back anyway. Also I have some zoas and palys, so those rocks I am not brushing for avoiding problems with palytoxin
 
OP
KonradTO

KonradTO

Well-Known Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 11, 2021
Messages
690
Reaction score
335
Review score
+0 /0 /-0
Location
Germany
Also I noticed that when I scrub the algae and the water gets dirty my new stylophora/seriatopora milka gets quite ticked and retracts the polyps for a while. I think it gets irritated from the strands that float in the water and end up attached to the frag
 

damsels are not mean

Valuable Member
Review score
+0 /0 /-0
View Badges
Joined
Nov 14, 2021
Messages
1,498
Reaction score
1,580
Review score
+0 /0 /-0
Location
Chicago
Also I noticed that when I scrub the algae and the water gets dirty my new stylophora/seriatopora milka gets quite ticked and retracts the polyps for a while. I think it gets irritated from the strands that float in the water and end up attached to the frag
Nah it's eating most likely
 

Lavey29

2500 Club Member
Review score
+0 /0 /-0
View Badges
Joined
Apr 29, 2021
Messages
3,206
Reaction score
2,736
Review score
+0 /0 /-0
Location
United States
Your water parameters are off which contributes to your GHA. Cut lights back to 8 hours with blue and UV only no white. Add another urchin and raise magnesium to 1500 which weakens GHA and makes it easy for you and the cleaners to remove. My tank was a complete covered jungle and these steps help strip it bare in 3 weeks.
 
OP
KonradTO

KonradTO

Well-Known Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 11, 2021
Messages
690
Reaction score
335
Review score
+0 /0 /-0
Location
Germany
Your water parameters are off which contributes to your GHA. Cut lights back to 8 hours with blue and UV only no white. Add another urchin and raise magnesium to 1500 which weakens GHA and makes it easy for you and the cleaners to remove. My tank was a complete covered jungle and these steps help strip it bare in 3 weeks.
Why do you say my params are off?
Also mg is already around 1500.
I can definitely turn off whites, but I guess that means I need to compensate with higher blue % to maintain par right?
For the urchin, are we sure we have the same algae? My urchin does not seem to eat much of the gha..
 
Reef Chasers Aquaculture

Lavey29

2500 Club Member
Review score
+0 /0 /-0
View Badges
Joined
Apr 29, 2021
Messages
3,206
Reaction score
2,736
Review score
+0 /0 /-0
Location
United States
Why do you say my params are off?
Also mg is already around 1500.
I can definitely turn off whites, but I guess that means I need to compensate with higher blue % to maintain par right?
For the urchin, are we sure we have the same algae? My urchin does not seem to eat much of the gha..
Because you have 0 nitrate per your post and low but measurable phosphate. I used 3 blue tuxedo urchins. I would hand place them in the jungle so they would have to eat their way out.

Are you sure you have GHA and not briopsis? I had a combo. Briopsis roots into the rock and much harder to remove. That is where 1500 magnesium helps.

Blues and UV should be at 100 for corals anyways
 
OP
KonradTO

KonradTO

Well-Known Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 11, 2021
Messages
690
Reaction score
335
Review score
+0 /0 /-0
Location
Germany
Because you have 0 nitrate per your post and low but measurable phosphate. I used 3 blue tuxedo urchins. I would hand place them in the jungle so they would have to eat their way out.
Well the ICP says 2ppm. Hard to tell the difference between 0 and 2 with standard kits.
Are you sure you have GHA and not briopsis? I had a combo. Briopsis roots into the rock and much harder to remove. That is where 1500 magnesium helps.
It does not look like bryopsis. Does it look like yours from the pictures?
Blues and UV should be at 100 for corals anyways
my light (viparspectra) cannot be kept that high in such a small tank. I use the settings suggested by other users (1%W, 15% blue). I will increase blue channel to 30 until I can turn whites back on, it should not hurt anyway.
Why is there a problem with the white channel btw in your opinion?
 
OP
KonradTO

KonradTO

Well-Known Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 11, 2021
Messages
690
Reaction score
335
Review score
+0 /0 /-0
Location
Germany
No last time I checked right after the blackout I had 0 nitrates and 0.04 po4 ...my macros probably get rid of them quickly. Also I recently added a ball of chaeto (2 weeks ago) and it doubled in size already. My guess is that nutrients are there but get depleted by macros and gha quickly. The problem is that is almost impossible to brush all the rocks with GHA, and in some cases I have palys so I do not dare to brush those.
That's why I am considering to use monthly/bimontly blackouts.
20220514_191051.jpg


20220514_191036.jpg
20220514_191047.jpg
it's GHA right?
 

Spare time

5000 Club Member
Review score
+0 /0 /-0
View Badges
Joined
Apr 12, 2019
Messages
7,221
Reaction score
5,155
Review score
+0 /0 /-0
Location
Here
I think it might be bryopsis or something not very palatable. Fluconazole is the best for bryopsis but some macro algae species do not tolerate it (some do though). Don't change your lighting or you water numbers except possible boosting nitrate if you are not feeding heavily (aminos are a great way to do this). Lighting is not a limiting factor for algae in a proper reef tank.


Could you post pics with only white light?
 

Dan_P

2500 Club Member
Review score
+0 /0 /-0
View Badges
Joined
Sep 21, 2018
Messages
3,310
Reaction score
3,752
Review score
+0 /0 /-0
No last time I checked right after the blackout I had 0 nitrates and 0.04 po4 ...my macros probably get rid of them quickly. Also I recently added a ball of chaeto (2 weeks ago) and it doubled in size already. My guess is that nutrients are there but get depleted by macros and gha quickly. The problem is that is almost impossible to brush all the rocks with GHA, and in some cases I have palys so I do not dare to brush those.
That's why I am considering to use monthly/bimontly blackouts.
20220514_191051.jpg


20220514_191036.jpg
20220514_191047.jpg
There might be more than just green hair algae. Would share a photo under white lights?
 
Aquarium Specialty - dry goods & marine livestock
Deltec

Peninsula Reef Tanks...

  • I currently have one

    Votes: 20 19.4%
  • I used to have one set up

    Votes: 4 3.9%
  • I would like to try one in the future

    Votes: 58 56.3%
  • No interest

    Votes: 21 20.4%
Top