Hammer coral not extending, help!

[lagona]

My Hammer coral hasn't been extending for about a week now. Water params are good, 0 ammonia, 0 nitrite, 5 nitrate, 8.2 pH, 1.025 salinity. Running a 75-gallon tank with two AI Prime 16HDs, 10-hour light cycle. No recent changes except a water change 5 days ago. Any ideas?

[seabird]

Could be flow related. What's your current setup? I had a similar issue with my Torch until I tweaked the powerhead placement. They like moderate, indirect flow. Also, what's your alk sitting at? Hammers can be fussy if it's swinging.

[buzzbee]

Alk is key here. Mine acted up when my alk dropped below 8. Test it ASAP. Also, check for pests like flatworms or nudis. They can stress the coral without being obvious.

[Lyrax]

Mine did that once. I just waited and it came back. Maybe it's just mad?

[fizzle]

I'd double-check the light intensity. Too much PAR can make them retract. What's your schedule like on the Primes?

[lagona]

Could be flow related. What's your current setup? I had a similar issue with my Torch until I tweaked the powerhead placement. They like moderate, indirect flow. Also, what's your alk sitting at? Hammers can be fussy if it's swinging.

Running two Nero 5s at 40% on opposite ends. Alk is stable at 8.5, tested yesterday. No pests spotted during dip last month.

[seabird]

Could be flow related. What's your current setup? I had a similar issue with my Torch until I tweaked the powerhead placement. They like moderate, indirect flow. Also, what's your alk sitting at? Hammers can be fussy if it's swinging.

Running two Nero 5s at 40% on opposite ends. Alk is stable at 8.5, tested yesterday. No pests spotted during dip last month.

Hmm, flow sounds fine. How old are the bulbs in your Primes? Spectrum shift can sometimes mess with them. Also, any chance it's getting stung by a nearby coral?

[buzzbee]

Second the sting theory. My Hammer got zapped by a Galaxea once and sulked for weeks. Give it some space if it's near anything aggressive.

[fizzle]

Second the sting theory. My Hammer got zapped by a Galaxea once and sulked for weeks. Give it some space if it's near anything aggressive.

Yep, same here. Moved mine away from a Duncan and it perked up in a few days. Try relocating it to a quieter spot.

[seabird]

One last thought, have you fed it lately? Sometimes a snack of mysis or reef roids can coax them out. Mine's a pig for frozen brine.