Hammer Corals Shrinking?

Ive had my green hammers for about 3 weeks now, immediately after I put them in my tank they were doing terrific. The larger of the two actually split from 3 to 4 heads about week in the new tank and had spread way out from what it had been in the LFS, I couldnt believe how great they were improving in my tank.

Then pretty suddenly about 5-6 days ago they starting shrinking. Just after I noticed them starting to retract, around that time I had to net a fish for treatment in a quarantine. The little guy was giving me a real hard time so I did have to move the corals around a bid so not to harm them. After that they just seemed to continue to pull in, which up until this point is very unlike them. Today I even noticed that my larger one seems like some of its tentacles have shriveled up a bit... I may be a little paranoid but also my large star polyp has not come out in the 3 days it has been since it was last moved...

This is the only photo of them from before they starting going down hill. You can really see how much larger the small hammer is. Both Hammers were easily 2x as big as they are now and im not sure if I should start to worry...




Here are the recent pictures









Water parameters are exactly the the same as always have been...

79 degrees
Salinity - 1.023
Ammonia - 0ppm
Nitrite - 0ppm
Nitrate - 0ppm
Phosphates - 100% Undetectable with my API test
PH - 8.2
Calcium - 420ppm
KH - 179ppm

Do you have enough light?

And how is the flow on them?

Bifferwine said:

Do you have enough light?

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I have about 4 watts per gallon using these T5's 1 - 460nm blue, 1 - UV Super Actinic 420 bulb, 1 - 12000k daylight, 1 Giesemann AquaBlue+

All corals are in the sand bed with the exception of the star polyp's.


The flow ive been trying to figure out... Seems like the hammers preferred when I had them in less flow so I have them positioned far from my power heads and water return, But they still gett a good bit of flow since its a small tank...

ya so you have 54w bulbs and have 4 bulbs which brings you to 216w which might not be enough for the hammer. you may need to upgrade lighting to a 6 or 8 t5 lighting system

i have heard the nova extreme lights are pretty good and its a 6 t5 light bulbs
Current USA Nova Extreme Pro T5 Aquarium Lighting Fixture, 6X54 Watt, 48 inch

Justinb2188 said:

ya so you have 54w bulbs and have 4 bulbs which brings you to 216w which might not be enough for the hammer. you may need to upgrade lighting to a 6 or 8 t5 lighting system

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I have heard some say that LPS require 6-8 watts per gallon which just isn't true, hammers don't preference strong light . 3 to 4 watts per gallon Is actually good for these. Also, there are many factors that determine how much and what kind of light is required like type of bulb, fixture, distance, water quality, tank shape, tank placement, light cycle etc...

Your lighting is just fine. I had 4 x 54 watt T5s over my old 55 gallon for years.

As you've noticed, they don't like a lot of flow. Too much flow can rip their flesh off the skeleton. Also, moving them around will keep them closed. Have you been bugging them? ;)

W theymight have to much flow move him every couple of days and see if he will open up

Bifferwine said:

Your lighting is just fine. I had 4 x 54 watt T5s over my old 55 gallon for years.

As you've noticed, they don't like a lot of flow. Too much flow can rip their flesh off the skeleton. Also, moving them around will keep them closed. Have you been bugging them? ;)

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I have been :( That was actually going to be my next question. Now that I have all fish I need into quarantine Im done moving everyone and it actually looked much better today!