Two months and my hammer coral won't inflate

[Nutmegs]

So here's what's been going on with my Hammer coral:

I had to temporarily relocate it to my QT about two months ago, and while it was there, a rock fell on it - no visible damage, but it definitely wasn't happy about it. Since then, it's been semi retracted and refuses to inflate.

The weird thing is, all my other corals - Frogspawn, Zoas, Ricordeas, Gorgonians, etc - are thriving. I've tried moving the Hammer to different areas of the tank, but nothing's working.

The color looks great, and it'll eat Mysis Shrimp if I spot feed it - it just won't inflate. My water parameters are:

Temp: 78
Salinity: 1.023
Nitrites: 0
Ammonia: 0
PH: 8.4
Nitrates: >.02ppm

Any ideas what's going on?

[talonix]

A few things to consider:

Is your Hammer coral getting enough light? I've found mine does best in the mid to top section of the tank. What's your ALK level - I'm curious if that might be a factor. And have you changed the flow in that area recently? Too much flow can be a real issue for these corals.

[Nutmegs]

A few things to consider:

Is your Hammer coral getting enough light? I've found mine does best in the mid to top section of the tank. What's your ALK level - I'm curious if that might be a factor. And have you changed the flow in that area recently? Too much flow can be a real issue for these corals.

He's about 10-12 inches below a dual T5, so I'm pretty sure he's getting enough light. I've tried placing him in different areas of the tank - bottom, near the top, and currently he's in the middle.

As for flow, I've positioned him as far away from the powerhead as possible, so it's minimal. There's still some flow, but it's definitely not too much.

You're right to point out ALK - I don't usually check that regularly. I'll make sure to test it today.

I'm curious, why would ALK affect the Hammer coral but not the other corals in the tank? I've got a JBJ 30 and do bi-weekly 5-gallon water changes, so my LFS told me I shouldn't worry too much about Calcium and Mag levels.

[talonix]

ALK can impact all corals, but Hammers often show stress first, before other corals like Frogspawn. If ALK levels are low, it won't be long before the rest are affected too - just a theory, not saying that's the case here.

Your LFS is right on Calcium and Mag levels, as long as you're lightly stocked. I was in the same boat, not dosing anything until about three months ago, despite having a bunch of corals, including SPS and LPS. At some point, you'll likely reach the same point, but for now, your water changes should be enough.

[Nutmegs]

Thanks for the insight, I had no idea Hammers were more sensitive like that. I'll get to the bottom of it, that piece of coral is definitely one of my favorites.

[lake1]

I'm no expert, but I think your salinity is a tad low - shouldn't it be around 1.026? And what about your tank temp - I've heard 79-80 is more ideal.

[felinxo]

I'm no expert, but I think your salinity is a tad low - shouldn't it be around 1.026? And what about your tank temp - I've heard 79-80 is more ideal.

I've got to agree with that, my Hammer's been playing up since the QT mishap and I've been racking my brain for a solution.

[finnix25]

If your salinity is 1.023, I'd be willing to bet that your calc, alk, and mag levels are all low. Most salt mixes are formulated at 35 ppt, so running at 31 ppt is going to result in a 12% drop across the board. This isn't necessarily a coral killer, but it will stunt growth and potentially impact health over time. Just because a coral looks happy doesn't mean it's in optimal health - think of it like a smoker who seems fine until they try to run a mile.

In a tank like yours, I'd recommend shifting your focus from testing ammonia and nitrite to calcium, magnesium, and alkalinity. pH can be a bit of a wild goose chase, so I wouldn't worry too much about that. Euphyllia corals thrive in stable environments, which can be tough to achieve in a smaller tank like yours. Keep in mind that salt mixes can vary from batch to batch, so dosing can help you maintain consistency.

The bottom line is that consistent, optimal levels of these chemicals will help keep your coral healthy and promote growth. Calcium and alkalinity are crucial for the formation of the coral's endoskeleton, while magnesium helps keep these chemicals available in the water column. A high-quality salt like Tropic Marin Pro, Red Sea Pro, or Seachem Salinity will generally produce chemical levels within the optimal range when mixed to 35 ppt (~1.0265), reducing the need for dosing. Euphyllia corals are relatively tolerant of water conditions, but they do seem to depend on stability.

[Nutmegs]

If your salinity is 1.023, I'd be willing to bet that your calc, alk, and mag levels are all low. Most salt mixes are formulated at 35 ppt, so running at 31 ppt is going to result in a 12% drop across the board. This isn't necessarily a coral killer, but it will stunt growth and potentially impact health over time. Just because a coral looks happy doesn't mean it's in optimal health - think of it like a smoker who seems fine until they try to run a mile.

In a tank like yours, I'd recommend shifting your focus from testing ammonia and nitrite to calcium, magnesium, and alkalinity. pH can be a bit of a wild goose chase, so I wouldn't worry too much about that. Euphyllia corals thrive in stable environments, which can be tough to achieve in a smaller tank like yours. Keep in mind that salt mixes can vary from batch to batch, so dosing can help you maintain consistency.

The bottom line is that consistent, optimal levels of these chemicals will help keep your coral healthy and promote growth. Calcium and alkalinity are crucial for the formation of the coral's endoskeleton, while magnesium helps keep these chemicals available in the water column. A high-quality salt like Tropic Marin Pro, Red Sea Pro, or Seachem Salinity will generally produce chemical levels within the optimal range when mixed to 35 ppt (~1.0265), reducing the need for dosing. Euphyllia corals are relatively tolerant of water conditions, but they do seem to depend on stability.

Thanks for the detailed advice, I really appreciate it. I do use Red Sea Pro, actually I buy it pre-mixed from my LFS, which explains the 1.023 salinity. I'm planning to get the right test kit and start tracking those parameters you mentioned, rather than focusing on pH.

This hobby can be tough, especially when you get conflicting advice from your LFS. It's kind of like when I was modifying my car - everyone had a different opinion on the best way to do things. In the end, I went with a proven setup and a reputable tuner, and it worked out great. Hopefully, I'll have the same luck with my tank.

Thanks again for the tips, I'm looking forward to making some changes and seeing how my coral responds.