Bleaching corals...is this too much light

RyanN · Jan 12, 2023

I upgraded from a 29 gallon biocube to a JBJ 45 gallon around Thanksgiving this year and quite a few of my corals are bleaching slowly. I went from 1 light on my 29 to 2 lights on the 45 and I'm wondering if maybe I overestimated the amount of light needed. All the corals are under more water than they were in the biocube but that probably doesn't reduce the par too much? I do not have a par meter. Corals that are bleaching are a tubbs stellata monti, Miami hurricane chalice, space invader chalice another chalice and some cyphastrea. Nothing is white but it's definitely losing color. Today I raised the lights about 6 inches to see if that helps at all. Does it look like I have these set too high? Come on at noon and off at 8. Thanks!

ShepherdReefer · Jan 12, 2023

Depends. Here is a video from WWC. Shoot, I cant find it. Look at their YouTube channel.

my86iroc01 · Jan 12, 2023

RyanN said:
I upgraded from a 29 gallon biocube to a JBJ 45 gallon around Thanksgiving this year and quite a few of my corals are bleaching slowly. I went from 1 light on my 29 to 2 lights on the 45 and I'm wondering if maybe I overestimated the amount of light needed. All the corals are under more water than they were in the biocube but that probably doesn't reduce the par too much? I do not have a par meter. Corals that are bleaching are a tubbs stellata monti, Miami hurricane chalice, space invader chalice another chalice and some cyphastrea. Nothing is white but it's definitely losing color. Today I raised the lights about 6 inches to see if that helps at all. Does it look like I have these set too high? Come on at noon and off at 8. Thanks!

Check your nutrient levels. That can cause bleaching too

KrisReef · Jan 12, 2023

Without a picture, this "bleaching" could easily be just faster growth (more white than color) in the skeletons vs a negative "bleaching" event. Turning down the light period is a safe thing in most cases but without pictures my precious advice could be totally wrong (again!)

We need pictures or for better prognoises

Edit: I once mentioned to my wife that I could grow coral more successfully if I had a par meter. To my surprize she answerered: "Get one then!" I had one delivered a few days later and she was surprized how much they cost but now she knows the par under our lights. Very helpful !

CoralB · Jan 12, 2023

What KrisReef said

Not knowing all other parameters and even if lighting schedule is good means nothing if there was a sudden change in the amount of lighting intensity .

bushdoc · Jan 12, 2023

It is possible to bleach corals with AI Prime ( I did it), but it usually takes just few days, not months. I would look for other causes too (water quality). Loosing color might be trace element or nutrition issue.

RyanN · Jan 13, 2023

I will get a picture later today. Been battling a bit of cyanobacteria for a while and I believe diatoms. Here are my parameters.
Alk - 8 (checked frequently)
PH - 8.2
Calcium - 400
Magnesium -1350
Salinity 1.025
PO4 - 0.02 (Hanna) I've been trying to raise this
Nitrate - 5

I only have 2 fish so low nutrient input. I want more fish but my clowns have been the only fish for almost 2 years so they're jerks

. I know this low fish load might be part of the issue. I dose nitrates and have been feeding "reef blizzard" hoping it will add some phosphates. I dose 20 ml of all for reef per day.

Duffer · Jan 13, 2023

Get rid of the green on the light will promote algae. Also I would turn down your whites.
What are your parameters?

RyanN · Jan 13, 2023

Duffer said:
Get rid of the green on the light will promote algae. Also I would turn down your whites.
What are your parameters?

I just posted parameters the same time you posted this, see above. I turned the whites down to try and help with the cyanobacteria. I turned the whites down maybe 2 weeks ago.

DanyL · Jan 13, 2023

Hey Ryan,

Your Calcium is slightly low, it's not enough to be the root cause of the symptoms you've been experiencing, but it may contribute to the problem. I would bump it to around 420-450 regardless.

All other parameters seem to be fine, so I would agree with your suspicion of too much light to be the cause of these symptoms.

The thing with Cyphastrea and Chalices is that they are low PAR (100-ish) corals which are able adapt to higher PAR (200-ish) as well, but it needs to be done slowley. They also don't seem to react well to changes in spectrum.
This is the reason why when I'm getting a new Chalices/Cyphastreas or other low PAR corals I would first place them in a slightly shaded area, then slowly over a months period (sometimes more) I would move them towards a more lighten area.

In your situation, due to the fact that you transferred from a different tank and added a second fixture, I would do a full acclimation for around 3 to 5 weeks, it would make sure all corals are adapted to their new environment.

Good Luck.