Hammer coral care and feeding

[bould]

I'm feeling pretty silly right now. I thought coral got most of its nutrients from photosynthesis and the symbiotic relationship with zooxanthellae, with a bit extra from the water column.

I grabbed a hammer coral at a frag swap over the weekend, assuming it just needed some light to thrive. But then I started browsing online for pics of hammer corals to compare with mine, since it doesn't seem to be opening up fully, and I stumbled upon vids of people feeding theirs mysis. Am I wrong for not researching this better? Should I rush out and get some mysis for target feeding, or is this something I can skip?

Also, what's the deal with lighting and flow for hammer corals? I've read they're supposed to be on the sand, which means low light, right? The thing is, my tank's 30 inches deep and I'm only running a 4-bulb T5 setup, so I'm worried the sand bed's not getting enough light. For now, I've got the hammer on a rock about 5 inches from the bottom, and it seems okay, but the polyp tips don't look as full as they do in most online pics. If I move it higher up, it'll get blasted by the powerheads.

[fleeton]

I've got a bunch of hammer corals, 7 in my tank and a few in my girlfriend's biocube. I started all of them on the sand bed, but my tanks aren't nearly as deep as yours, so I'm not sure how that'll play out for you. Lighting-wise, my girlfriend's biocube has the factory lighting - actinic and 10k - and my 55g has 2 ATI blue plus and 2 ATI coral plus. I've placed all of my hammers in low flow areas, they don't like too much flow or they won't fully extend. Some of mine extended fully within an hour or so, but some took about a day to adjust to the new conditions. I try to target feed them mysis about once a week with a small pipette. How long has your hammer been in your tank? Is it a branching or wall type? I've also noticed mine don't fully extend when I have half the lights off in the morning, once all the bulbs are on, they extend fully.

[bould]

It's been 3 days since I put the hammer in the tank, Saturday to be exact. I'm having a tough time finding a spot that doesn't get blown around too much - it's getting pretty rough treatment no matter where I put it. Right now it's in a relatively protected spot, but the only way I can think of to get it in really low flow is to tuck it in behind a rock.

Is the mysis just for an extra boost or is it something I need to be doing regularly?

[felinxo]

I'd say target feeding is more of a bonus for extra growth. The majority of the coral's nutrition still comes from the symbiotic relationship and photosynthesis, so the light is key.

[bould]

Thanks felinxo, that helps a lot.

[sweetie_22]

Felinxo is spot on.

I'd like to add that, in my experience, life forms that have mouths and tentacles capable of capturing food can benefit from occasional feeding.

[bould]

I'm getting really worried about this hammer coral now. It's been a few days since I got it, and it just won't open up like I've seen in pictures. The zoa and monti are doing great, but this one seems to be shrinking. I tried moving it to a spot with less flow, but that hasn't helped at all. I'm thinking maybe it needs more light - should I try moving it up higher in the tank?

[felinxo]

Hammers can be quite the challenge. I'm guessing you've got a wall hammer on your hands. I'd advise against moving it up higher for more light, to be honest. Wall hammers are notoriously finicky, with a mortality rate that's pretty steep - we're talking around 90% or so. And even if you do manage to keep it alive, long-term captivity can be a real struggle.

[bould]

Honestly, I thought hammers were pretty low maintenance. If they're actually that finicky, can you recommend a hardier soft coral that still has some movement? I really like the way they sway.

[sweetie_22]

I'm feeling pretty silly right now. I thought coral got most of its nutrients from photosynthesis and the symbiotic relationship with zooxanthellae, with a bit extra from the water column.

I grabbed a hammer coral at a frag swap over the weekend, assuming it just needed some light to thrive. But then I started browsing online for pics of hammer corals to compare with mine, since it doesn't seem to be opening up fully, and I stumbled upon vids of people feeding theirs mysis. Am I wrong for not researching this better? Should I rush out and get some mysis for target feeding, or is this something I can skip?

Also, what's the deal with lighting and flow for hammer corals? I've read they're supposed to be on the sand, which means low light, right? The thing is, my tank's 30 inches deep and I'm only running a 4-bulb T5 setup, so I'm worried the sand bed's not getting enough light. For now, I've got the hammer on a rock about 5 inches from the bottom, and it seems okay, but the polyp tips don't look as full as they do in most online pics. If I move it higher up, it'll get blasted by the powerheads.

Just to clarify, hammers are actually considered a type of hard coral, not soft, due to their calcium skeleton. Most Euphyllia species, like torches and frogspawn, are relatively easy to care for, even among hard corals. Branching hammers, in particular, seem to do well.

If your hammer coral isn't acclimating well, I think it's worth taking a closer look at your water chemistry. Key parameters like alkalinity, calcium, and magnesium are crucial for stony corals, in addition to the usual suspects like temperature, salinity, and pH.