Pumping Xenia stopped pumping

[reefaddict]

I have some tank raised pumping xenia I bought about 7 months ago. It is a fast growing excrusting species that I cultivate and sell back to my LFS. It has helped pay for my hobby... 4 days ago it stopped pumping. Has anyone seen this before?
Tank Parameters.
Temp 75 - 78
SG 1.024
Ammonia 0.0
Nitrite 0.0
Nitrate 0.0
Phosphate < 0.1
Calcium 400
Alk 3.2
PH 8.0 - 8.4
Iodine 0.2

[reefaddict]

ctenophore,
PH swings are normal during the course of the day. Increased photosynthesis by Zooanthlai (sp) raises Oxygen content of water which raises PH during your photo peroid. I know the presise swings because I have a electronic PH meter constantly monitoring this tank.
Temp is an interesting question. I keep my reef at the temps suggested from long ago (I have been reef keeping 17 years even though this tank is only 2 years old - I have several reefs.) and in TRA. I have seen Ron Shimeks articles about raising the temp and have been considering it. But this coral pumped for 7 months under these conditions.
The xenia is fully open, just not pumping.
I can't tell is growth has slowed down yet. It has only been 5 days.

Oh the lighting in this 90 gallon reef is 4 X 96 CSL PC's (retro). I keep the xenia in the upper quadrant.

[hcs3]

how old are the bulbs? i've seen xenia stop pulsing as the light drops off. for instance, the same species xenia in my tank acts completely different depending on the amount of light it recieves. the xenia that is literally growing out of the water pulse as if it just ran a marathon, yet the same exact xenia - cuttings from the mother colony - when placed lower in the tank stop pulsing.

HTH

henry

[reefaddict]

Interesting idea Henry,
The PC Bulbs are 9 months old. I was planning a slow phase in of new bulbs. 1 a week for 4 weeks. I was hoping to start in January but I may just start today.
Thanks

[TimS]

Mine grow and pulse nicely with your general tank paramenters. Two suggestions, pH - I've read that they like it more in the 8.4 range. How often are you at 8.0 and how accurate is your meansurement. My low reading with a monitor is 8.2. Also, I dose iodine daily (20 drops in a 180 gallon tank). Don't know what test reading this give me, but the Xenia is triving. How accurate is that iodine reading.

Good Luck.

TimS

[reefaddict]

Tim,
My PH flutuation from 8.0 - 8.4 runs a 24 hour cycle. I would say it is 8.0 for about 1 - 2 hours right before lights on and rises to 8.4 in about 6 hours. I have a 14 hour photoperiod so it is 8.4 for quite a while.
I have always noted that xenia pulses best at higher PH.
My PH measurement is being taken by an American Marine PH controller, that I use to control CO2 to my Calcium Reactor. I have calibrated it just 2 days ago.
My Iodine test kit is a seachem test kit. the kit contains a "base" for measuring your kits performance and it has been OK in the past.
I dose Iodine weekly using Kent Iodine (I know they make a couple of products and I can't remember the exact name of the one I use on this tank)
PS, I went home at lunch and changed one of my 96watt PC bulbs...

[Larry M]

ct--How do you know what your iodine levels are if you are relying on food for input?
;)
My ph runs low--7.85 to 8.15, and my xenia pulses like mad. I never add iodine. My MH bulbs are a year + old. Go figure.

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Larry M

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[TimS]

How is the Xenia doing? I was reading an article in AFM last night that had a sidebar about Xenia - they said that pulsing is affected by light intensity and color. They pulse under blue light stop under yellow light.

TimS

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There's No Place Like Home.

[Ewan]

Here's my ideas, just to add to the others.

first, let me say I would have though it was the pH, but you seem to have that avenue well addressed.

1. GAC, do you use it, have you recently changed it?

2. you might wish to try a powerhead on a timer generally pointed toward the colony. My Xenia really responded to this by incredible pulsing.

fwiw, I've read that it's not uncommon for Xenia to stop pulsing in captivity, yet still remain healthy.

keep us posted.

E.

[reefaddict]

Thanks to all who have posted....

I do not use GAC, as I know this will remove many of the DOC's that the xenia feed upon.

I have a wavemaster pro running 3 powerheads in the tank. One is pointed directly at the mother colony. (which has started to climb the back wall)

Good News, After changing the 9 month old PC bulb directly over the main colony, I have started to see pulsing again. (Thanks Henry) I have made no other changes, but there have been changes made... read on...

Comparing the visual light intensity of the new bulb against the older bulb, I see a noticable increase of light output. I don't have a lux meter so my accounting is rather unscientific.

In regards to PH, this past week it has been rather warm in my part of the US, and I have had much less evaporation. I also note an overall change in my PH swing. It has been more moderate... 8.12 - 8.28. A little low in my books for xenia pulsing, but they are pulsing. Because of the lower PH, my calcium reactor has not been adding CO2 to the mix.

I have made no assumtions here, just observations.

Thanks Again

Connor