Need help with my Frogspawn receding :(

[L0stNoodle]

A few days ago, I forgot and left my pump off after feeding. The heater was still on but since the water level was uneven, the temperature dropped to around 74F degrees for about 10 hours. Since then, my frogspawn has been receding heavily and I’m not sure what to do to help it. All the other corals are puffy and fine.

Pump left off on 5/29 night, turned back on 5/30 morning

water tested on 6/4
phosphate .1
nitrate 5.8
salinity 1.025
11dKH
Calcium 430

today is 6/6 and it’s more receded and I’m worried. If anyone has insights, please help

white light picture is today, blue light is 6/4

 

[Mr. Mojo Rising]

Unfortunately its more than just receded. Personally I would just leave it alone and hope for the best, but you might possibly lose it.

 

[Shirak]

How long have you had it?
74 degrees for 10hrs won't cause this.

 

[annihil8ted]

I agree, temp drop shouldn't have caused this.

If it hasn't been there for long, I would guess possibly too much light to quickly and would sink it to the sand in relatively low flow and see

 

[L0stNoodle]

How long have you had it?
74 degrees for 10hrs won't cause this.

I bought it on April 20th. It was fine before the pump incident and has been receding more and more after the incident til now. It’s still receded but I still see some tissue with a lot of skeleton so I think it’s just in major distress but can’t figure out why. I’ve turned the flow down to see if it helps. I’m staying consistent in what I’ve done before this started in hopes it’ll recoup itself

 

[L0stNoodle]

I agree, temp drop shouldn't have caused this.

If it hasn't been there for long, I would guess possibly too much light to quickly and would sink it to the sand in relatively low flow and see

This is a picture of it a few days after I got it in April. Maybe I could lower it in the tank, but my PAR for the top of my tank only goes up to 80. The range is 50-80 during the light schedule

 

[vetteguy53081]

A few days ago, I forgot and left my pump off after feeding. The heater was still on but since the water level was uneven, the temperature dropped to around 74F degrees for about 10 hours. Since then, my frogspawn has been receding heavily and I’m not sure what to do to help it. All the other corals are puffy and fine.

Pump left off on 5/29 night, turned back on 5/30 morning

water tested on 6/4
phosphate .1
nitrate 5.8
salinity 1.025
11dKH
Calcium 430

today is 6/6 and it’s more receded and I’m worried. If anyone has insights, please help

white light picture is today, blue light is 6/4

Not sure on the age of this tank but if newer, these are not ideal first corals and light and water flow play an important role. Moderate recommended for both. This is tissue recession and often due to stress - Not bailout. What are stressors?
Hammers are intolerant to major swings in water quality, and sensitive to almost any level of copper in the water especially if any tap water was added. Calcium and alk are important parameters that will affect their growth and this coral will start to die off if calcium levels are too low which should be about 400 ppm.
Basically, avoid bright light and water flow and dark lighting. Bright lights cause bleaching and low lighting will cause them to shrink and starve. Maintain moderate light for their photosynthesis and keep it off the sand bed which sand can irritate it.
I suspect your Po4 if accurate is causing issues

 

[L0stNoodle]

Not sure on the age of this tank but if newer, these are not ideal first corals and light and water flow play an important role. Moderate recommended for both. This is tissue recession and often due to stress - Not bailout. What are stressors?
Hammers are intolerant to major swings in water quality, and sensitive to almost any level of copper in the water especially if any tap water was added. Calcium and alk are important parameters that will affect their growth and this coral will start to die off if calcium levels are too low which should be about 400 ppm.
Basically, avoid bright light and water flow and dark lighting. Bright lights cause bleaching and low lighting will cause them to shrink and starve. Maintain moderate light for their photosynthesis and keep it off the sand bed which sand can irritate it.
I suspect your Po4 if accurate is causing issues

Running this tank since November 2025, had this coral since April and it was doing fine until now. I’ve had some issues with my nutrients bottoming out, but I use Hanna testers so it should be accurate. Calcium is 430ppm but Calcium is from API test kit so may not be completely accurate. I did my weekly 10% water change and it seemed to have puffed up a tiny bit? but it went back to showing skeleton the next day. I included the picture after the water change. I’m thinking maybe do 20% water change for the next one to lower nutrients? what do you think?

Also, I have another hammer coral that is doing fine in the tank. I know they’re not quite the same but,

 

[LiP]

It’s a good sign of recovery. I would closely monitor if algae would attach on the exposed skeleton.

 

[Shirak]

IMO .1 phosphate is not an issue. The low nitrate most likely. Your comments on Par are also concerning. Generally looking around 120-150 par for these corals. 80 at the top of the water is very low. Par drops off quickly as you go further down into the water. Nutrients bottoming out is also an issue. Nutrients needed by the corals are also used by algae and the new tank with the nutrient swings and algae popping up on newish rock will cause these swings when feeding is light and fish bioload is not very high. If it comes out I would look at maybe spot feeding these corals 2 or 3 times a week with lps pellets or frozen mysis. Turn the pumps off for 20 min or so. From my experience hammers and frogspawn like to eat during the day when the tentacles are extended.

 

[Privateye]

I agree that having the tank not running for 1 night is not the source of this issue. It could have been a small stressor, but these things are shipped overnight in bags. It should be okay. I lost power for 8 days once and I did lose 1 euphyllia out of 3 after 1 week without flow, light, or temperature control (the house got to nearly 90 degrees without air conditioning).

Water parameters could be a factor, and improving them is worth pursuing either way, but I'd treat it to be on the safe side. An iodine dip followed by a melafix dip is what I'd do. I've seen that halt slow tissue necrosis in SPS. And they're pretty safe dips so I wouldn't expect them to cause any issues.

 

[BryanM]

This temp issue would do this.

Your light is low, par at the bottom of your tank should likely be in the 80-110 range, so 80 at the top = insufficient light, and light is what fuels these corals.