All my M. caps suddenly brighter--is this 'bleaching?'

[Gyr]

I recently tried my first wet-skim method water change. Over about 6 hours I let my skimmer pull off about 10% water volume from my system, replacing with fresh SW using my ATO system. Within 24 hours all my M caps became REALLY bright. My green with purple rim cap has gone from generic green to a bright teal and my purlple cap from a deep purple to bright lavender. This all occured about 5 days ago now and the colors haven't changed since. The rest of the tank seems stable/improved since the wet-skim. BTA bigger and plumper than usual, much less dusting of algea on glass than I am used to.

I have been lucky enough to never have a coral bleach, so I am wondering if this color change is a sign of stress/early bleaching. If so, should I stop skimming for a few days? Stop my GFO and/or GAC? Should I just relax and enjoy the bright new colors (even though they are so bright they look kind of phony).

Here are some pictures.

Current color of green with purple rim cap and you can see part of the purple cap in the image...

Here's what the green with purple rim cap usually looks like:

This picture shows what the purple m cap usually looks like (and you can see part of the green on in the lower left corner of the photo.

I have tested and re-tested all my parameters, all remain normal and there have been no other changes in my routine, other than that wet-skim water change.

Thanks, in advance, for any advice.

 

[Gyr]

Bump

Bump

Anyone?

Sorry about being impatient, but I am leaving town for several days tomorrow and was wondering if I should make any adjustments to my system (skimming/GFO/GAC) before I go.

Thanks

 

[GhostCon1]

Um, if the color is accurate, that monti cap is 100% bleached out.

 

[Gyr]

GhostCon1 Um, if the color is accurate, that monti cap is 100% bleached out.

Yeah, I am afraid that is what the color actually is. Bummer. I can't figure out what caused the bleaching. Except for the wet-skim water change, I haven't done anything different and parameters all stable (SG = 1.025, pH = 8.2, ALk = 10, Ca = 420, Mg = 1300, Nitrate = 0, PO4 = 0). That leaves me thinking it was the wet skim, but I am not sure why that would do it....

Should I cut down on any of my nutrient exporters? Decrease my light cycle?

 

[GhostCon1]

How long have you had the cap? How long is your light cycle?

Try lowering your alk down to 9 and see if that helps.

 

[allsps40]

Have you made any other changes? Like lighting, dosing or anything other that the auto water change?? Check you SG make sure it is still good. Bleached for sure, but I dont see how a water change could cause bleaching. Unless the new water was out of parameters.

 

[MammothReefer]

Raise your mag, drop your alk...at least that is what I would do.

 

[Roll221]

Calibrate your refractometer, that was the cause of a similar headache for me. Was doing water changes with SG of 1.034.

 

[Rosh]

Calibrate your refractometer, that was the cause of a similar headache for me. Was doing water changes with SG of 1.034.

Oh wow, that must have stressed out your fish.

 

[prickles]

That leaves me thinking it was the wet skim, but I am not sure why that would do it....

Should I cut down on any of my nutrient exporters? Decrease my light cycle?

Isn't one potential problem with running zeo or the like that it decreases DOC too quickly? This supposedly increases light penetration, which could cause bleaching. So if you wet skimmed all the bad stuff out, you essentially sunburned the corals?

possible answer?

 

[Gyr]

I'm back from my trip and the corals all look about the same as they did 4 days ago, except the purple cap is possibly a little less bleached. Nothing looks any worse.

GhostCon1 How long have you had the cap? How long is your light cycle?

--I've had the green cap for about 2 years, the purple about 1.5 years. Both started from small frags. My ATI has been running 12 hours on the 2-bulb dusk/dawn feature, 9 hours on the full 6 lights. It has been that way for several months. I did cut the full daylight cycle to 8 hours and raised the fixture 2 inches just before leaving on my trip 4 days ago (I felt I had to do SOMETHING).

allsps40 Have you made any other changes? Like lighting, dosing or anything other that the auto water change?? Check you SG make sure it is still good. Bleached for sure, but I dont see how a water change could cause bleaching. Unless the new water was out of parameters.

--I hadn't made any other changes to the system before the bleaching happened. I always verify that my fresh SW and old tank water have very similar SG (within 0.001) whenever I do my water changes, including the wet-skim technique I tried. I used Reef Crystals mix like I always have for the past few years. Except for checking the SG, however, I don't test the other paramaters of the fresh SW. I have checked the tank's parameters several times since then and all remain about where they normally have been.

MammothReefer Raise your mag, drop your alk...at least that is what I would do.

--I've adjusted my ATO fresh water to have a bit less alk in it. That should slowly bring the Alk down in the DT. I will also increase my frequency of supplementing the Mg, try to keep it in the 1350-1400 range (I've always shot for 1250 - 1300).

Roll221 Calibrate your refractometer, that was the cause of a similar headache for me. Was doing water changes with SG of 1.034.

--I always calibrate my refractometer before measuring tank or replacement water. I was surprised how much it changed from day to day when I first got it.

prickles Quote:
Isn't one potential problem with running zeo or the like that it decreases DOC too quickly? This supposedly increases light penetration, which could cause bleaching. So if you wet skimmed all the bad stuff out, you essentially sunburned the corals?

possible answer?

--This seems to make the most sense to me. Honestly, nothing else had changed with my tank when I tried this new technique. The favorable changes to my system after the wet skim water change (healthier-looking rose BTA and much less algea growth) speak to a much lower nutrient level than my tank has had in the past. The quick drop in DOCs/increased light penetration/'sunburned' caps theory really seems to fit with my observations.

Thanks for taking the time to provide your input every one....

Now the question remains; I am due for my next water change. Do I go back to the standard technique or do I assume the corals will adjust to the lower DOCs and do another wet-skim water change?

 

[Oldtimer]

prickles Quote:
Isn't one potential problem with running zeo or the like that it decreases DOC too quickly? This supposedly increases light penetration, which could cause bleaching. So if you wet skimmed all the bad stuff out, you essentially sunburned the corals?

possible answer?

--This seems to make the most sense to me. Honestly, nothing else had changed with my tank when I tried this new technique. The favorable changes to my system after the wet skim water change (healthier-looking rose BTA and much less algea growth) speak to a much lower nutrient level than my tank has had in the past. The quick drop in DOCs/increased light penetration/'sunburned' caps theory really seems to fit with my observations.

... I agree with this. I am facing the same issue which I suspect is related to my overkill skimmer, fuge+DSB, GAC, RO/DI water, meticulous maintenance and light feeding coupled with a low fish load and 450 gallons of water. I'm just trying to get more food in the system now, frag a few corals that STN'd and cut the photo period back (although after further thought I plan to add some mesh screens to the top of the tank and keep the photoperiod longer). Most of my acros bleached from the tips down. It actually started with a birdsnest and then a couple monti's started to bleach. Then some of the bleached tissue started dying and a couple acro's started to STN from the base up. Polyp extension is also lacking, but they seem to perk up slightly when the halides switch off and the supplemental (2x 80W) T5's are on.

I think you very well could have stripped the water clean so to speak... fortunately it looks like you did not suffer any losses. I think your heavy bioload helped you out. In my case, cutting back the skimmer operation and throwing more food into the system seem to be in order.

 

[Gyr]

Thanks for the advice, oldtimer. As soon as I came to the 'conclusion' that my caps bleaching was probably from a sudden drop in DOCs, I upped my feeding regimen from once/day Rod's to twice/day and a piece of Nori for my two tangs.
I do ultimately want to get my DOCs as low as I can and plan to use the wet skim water change techinque again (nothing else I have done has had as big of an impact), I just don't know if I should wait a few weeks, doing regular water changes in the mean time.
Also, it seems that most people with ultra low nutrient tanks dose amino acids. I better do some more reading about that as I am not sure what the AAs are supposed to do, exactly, or which are the better AA products to use...

I guess that is one of the reasons I enjoy this hobby so much. Always more to learn.

 

[Gyr]

I'm glad to say that my monti caps are well on their way to recovery from the bleaching episode. Working on the 'sunburn from too rapid drop in DOCs due to the wet skim technique' theory, I fed the fish heavier for a while, did a regular water change on the following week, decreased the lighting, etc.
The bleached colors remained stable for about a month, then started to improve. I really liked the way the rest of my system responded to the wet-skim method of water changes, so I went back to it pretty early on. It didn't seem to shock the caps on subsequent trials, and that's the way I've been doing my water changes since.

Here's a current shot of the caps that I posted at the begining of the thread. The green cap isn't quite as rich as it originally was, but it is getting pretty close. I'd say the purple cap is fully recovered.

Thanks again, everyone for taking the time to give me your opinions and advice.

 

[Jfishdr]

The other colors look great. Do you have a FTS?

 

[Gyr]

Jfishdr The other colors look great. Do you have a FTS?

Thanks for the compliment. I have tried several times to get a good FTS in the past, always with poor results. Through-the-glass seems to be the main problem for my limited skills/low-end camera, but I think my coral frags are still too small to show up well in a full shot of my 6 foot tank. I'll give it another try and if I get a halfway decent shot, I'll post it.

Thanks again.

 

[coralreefhq]

Looks a bit bleached to me, probably from lighting.

 

[Dustin1300]

Looks a bit bleached to me, probably from lighting.

Did you even read the thread?

Gyr, I've suffered a similar disappointing bleach with my caps recently because of a change in ballast which really seemed to increase my lighting much more than I realized. On a good note, I'm glad you discovered the problem and curious how long the setosa has been growing out? I picked up a very small frag and has continued to encrust but has not started sprouting vertically in two months. I'm just curious of how long it took to grow out and not trying to hijack!

 

[Gyr]

Hey Dustin, I'll have to check my log on my home computer when I get off work tonight, but I am pretty sure I have had that Setosa for about a year. It was about 3/4 - 1 inch frag when I got it. It has been a fast grower in my system and I have fragged 3 pieces from it to spread around in my tank. The 3 frags are basically encrusting the rock work, not really getting the finger-like projections you see in the photo. I'm not sure how long it took for that piece to develop the projections, but I do take photos of my corals every month or two and I should be able to give you a better answer when I get home and take a look at them.
Interestingly, that monti never really showed any significant bleaching like the caps did.

 

[Gyr]

I'm a doof. When I got home and looked in my tank, all my Setosa frags are showing branching growth, not really encrusting all that much. I got the frag in November, 2010. Here is what it looked like then:

Here's a shot a few months later, showing that it's been having horizontal projections growing out from the base basically from the begining:

So I guess my setosa specimen has a tendancy to branching growth, at least in my tank. It sure is an interesting (and beautiful) monti. Good luck with yours,