One section of GSP is no longer happy

[Der]

I am wondering if anyone can help... In my mixed reef (13.5 gallon Evo), I have GSP on my back wall in a few sections. One section is thriving, fully extended, and happy. The other sections are not... You can see one section in the back of the picture. I'd say they are in comparable lighting and flow. These non-happy sections were previously just as happy and were growing along the glass. The parameters I measure are all within normal ranges, I recently did a 25% water change and my other corals are happy. The tank is 10 months old and has been fairly stable. I did drop my nutrients to 0 more than a month ago because I added chaeto. Now I feed more and dose NeoNitro and have recovered fully from the dinos.

Part of me wonders if the GSP is losing a battle to the algae/bacteria growing on my back glass. I haven't cleaned it off because the glass isn't painted black and it kinda helps with that.

Any thoughts or ideas?

 

[KrisReef]

Yup, it looks "surrounded" on the glass with algae?

If the challenge is water quality perhaps carbon or polyfilter might improve conditions? Same thought with UV.

 

[jimeah]

Without seeing the tank irl, it looks like the second piece is in less light or shaded?

In my last tank I had a huge algae issue, hair, bubble you name it, nothing stopped my GSP from expanding, and it doesn’t look like the algae is on the coral tissue either.

During the water change was the GSP exposed to the air? If mine gets exposed it sulks for a few days.

I’ve never cleaned the back wall of my aquarium, I prefer to leave it as a field of algae so that my grazers permanently have access to it. In the last tank I had stuck all sort of coral on the back and algae never overtook them.

Nutrients being too low and having to “dirty up your water” and heavy-in heavy out is currently trending with great success, so the previous advice with carbon etc. might be counter intuitive IMO.

I think the prescription is patience, unless you see die off of the purple tissue underneath.

 

[Der]

Yup, it looks "surrounded" on the glass with algae?

If the challenge is water quality perhaps carbon or polyfilter might improve conditions? Same thought with UV.

It is surrounded. I'm running filter floss and UV for 12 hours each day

 

[Der]

Without seeing the tank irl, it looks like the second piece is in less light or shaded?

In my last tank I had a huge algae issue, hair, bubble you name it, nothing stopped my GSP from expanding, and it doesn’t look like the algae is on the coral tissue either.

During the water change was the GSP exposed to the air? If mine gets exposed it sulks for a few days.

I’ve never cleaned the back wall of my aquarium, I prefer to leave it as a field of algae so that my grazers permanently have access to it. In the last tank I had stuck all sort of coral on the back and algae never overtook them.

Nutrients being too low and having to “dirty up your water” and heavy-in heavy out is currently trending with great success, so the previous advice with carbon etc. might be counter intuitive IMO.

I think the prescription is patience, unless you see die off of the purple tissue underneath.

Appreciate the input. The second piece should actually have more light where it's located. I'm happy to hear you've let your back glass algae go wild because I also like to leave it for CUC and copepods/amphipods. It would've been exposed to air for a short bit during the water change so it's possibly just ticked. I will be patient and see if it improves then.

 

[kevgib67]

Appreciate the input. The second piece should actually have more light where it's located. I'm happy to hear you've let your back glass algae go wild because I also like to leave it for CUC and copepods/amphipods. It would've been exposed to air for a short bit during the water change so it's possibly just ticked. I will be patient and see if it improves then.

I’ve had mine in my tank coming up on 3 years. It periodically gets moody and closes up for a day or two for no apparent reason while many much more difficult corals are as happy as ever. If you were to kill your GSP figure out what did it and write a book titled “ how to kill and rid your tank of gsp,” you’ll be a millionaire!