The curios case of the disappearing GHA

[arking_mark]

Over the last 3 months, my GHA issues which has been ongoing for about a year (Sept 2022) has completely disappeared with no change in my tank maintenance (this is a very automated system). Some interesting observations during this time:

• The GHA seemingly suffocated out all but one colony of Zoas
• Two SPS colonies browned out. One recovered the other one bleached out.
• All other SPS and corals continue to grow very well

So I'm guessing something happened to the biom and the bacteria has now shifted back to a healthy biom that outcompetes the nuisance algae.

Thoughts?

From my previous thread...

I've been trying to figure out the source of my nuisance algae issues (GHA and bubble Algae) which started back in Sept 2022. Prior to this time, the tank had been up and running for a little over 21 months with no issues or ugly phases. For a good portion of this time the tank was running as an ULNS. As I increased biodiversity and such, the tank has mostly settled in at around <1 ppm NO3 and <0.05 PO4 with occasional too low or above these nutruent targets that required some adjustments. The bubble algae was taken care of by using Emerald Crabs, but I have not been able to eliminate the GHA despite my best attempts that included manual removal, refreshing and augmenting my cleanup crew (snails, crabs, urchins, etc...). Now to be fair, the GHA isn't taking over the tank or anything, but present enough that I would like it gone.

Could phyto dosing be the source of my nuisance algae?

I've been trying to figure out the source of my nuisance algae issues (GHA and bubble Algae) which started back in Sept 2022. Prior to this time, the tank had been up and running for a little over 21 months with no issues or ugly phases. For a good portion of this time the tank was running as an...

www.reef2reef.com

 

[Lavey29]

Typically when GHA has run its course usually around the one year mark it gets replaced by coralline which out competes it if conditions are favorable.

 

[arking_mark]

Typically when GHA has run its course usually around the one year mark it gets replaced by coralline which out competes it if conditions are favorable.

I'm not sure that is what happened here. My coraline algae was well established prior to the GHA.

 

[Lavey29]

I'm not sure that is what happened here. My coraline algae was well established prior to the GHA.

Maybe the corraline finally won the battle then and will expand more. This is what happened to my GHA also.

 

[arking_mark]

Maybe the corraline finally won the battle then and will expand more. This is what happened to my GHA also.

Before...

After...

 

[Lavey29]

Looks good, I see the coralline on the back wall maybe it will cover that rock now too

 

[arking_mark]

Looks good, I see the coralline on the back wall maybe it will cover that rock now too

Lighting is too bright for coraline algae on the rocks...

 

[Lavey29]

Lighting is too bright for coraline algae on the rocks...

Perhaps, I run my radions at 100% intensity and still get coralline all over my rocks but the urchins keep it in check

 

[arking_mark]

Perhaps, I run my radions at 100% intensity and still get coralline all over my rocks but the urchins keep it in check

I only seem to get coraline algae in the shaded parts of my tank...

 

[Randy Holmes-Farley]

It is possible the GHA used up some chemical needed by them, which which corals are able to get by with lower levels in the water.

 

[arking_mark]

It is possible the GHA used up some chemical needed by them, which which corals are able to get by with lower levels in the water.

It's possible. However, over the last year, NO3 has almost always been < 1 and PO4 < 0.1 and usually much lower. It's typically close to a ULNS.

 

[Randy Holmes-Farley]

It's possible. However, over the last year, NO3 has almost always been < 1 and PO4 < 0.1 and usually much lower. It's typically close to a ULNS.

Maybe it's even lower now, or maybe it's a trace element such as iron or manganese that is limiting the GHA.

 

[arking_mark]

Maybe it's even lower now, or maybe it's a trace element such as iron or manganese that is limiting the GHA.

Clean ICP tests...no issues with Fe or Mn.

https://www.triton-lab.de/en/showroom/icp-oes/189882

 

[Randy Holmes-Farley]

Clean ICP tests...no issues with Fe or Mn.

https://www.triton-lab.de/en/showroom/icp-oes/189882

The issues I mentioned was being too low, and the icp detects none, so it may be too low.

 

[Court_Appointed_Hypeman]

I put my money on depleted iron

Edit: just saw the ICP, def think its iron, mine all disappeared when it reached 0 as well. Only realozed it was an issue becayse my nutrients started skyrocketing and my chaeto stopped growing.

 

[Court_Appointed_Hypeman]

Curious if you dose Iodine. I would expect it to also be 0 if your iron is depleted. Not that they have a similar method of action, but mostly because iodine depletes rapidly in my system, afaik quicker than iron.

 

[arking_mark]

The issues I mentioned was being too low, and the icp detects none, so it may be too low.

My Fe and Mn has been 0 forever...here is my ICP test from Jan 2023 (3 months into my issue...)

https://www.triton-lab.de/en/showroom/icp-oes/183655

 

[Randy Holmes-Farley]

My Fe and Mn has been 0 forever...here is my ICP test from Jan 2023 (3 months into my issue...)

https://www.triton-lab.de/en/showroom/icp-oes/183655

Yes, and Triton cannot detect down to natural level of iron , which leaves you knowing nothing other than that they are not above the detection limit.

 

[arking_mark]

Yes, and Triton cannot detect down to natural level of iron , which leaves you knowing nothing other than that they are not above the detection limit.

I didn't know that.

So I had no nuisance algae for two years then 1 year of nuisance algae...then it's gone again. Theory is trace elements?

 

[nuxx]

It got really bad in my tank about 12-16 months in, then went away pretty much forever...