Bleached Coraline Algae -A Sign Of......?

[DiverDude]

I've noticed a lot of my coraline algae is fading in colour -some is almost white.

Is this indicative of something I should be concerned about ?

This is happening in my tank also, will be following this thread.

[Reef_kid]

hey bleaching Coraline can be due to many reasons.

1. phosphate, and nitrate are very common. (keep them at zero!)
phosphate remover ! and a refugium works very well!

2. calcium levels and ph levels out of optimum range (calcium up above 400 and
ph8.1-8.3)



3. lighting is major issue in Coraline algae.

notice how purple it is. this is because the Coraline algae often absorbs wavelengths of light within the blue/purple/red spectrum. the pigmentations absorb these wavelengths and express there proteins (pigments).

often you will get green Coraline algae if you have a green/yellow ting to your light bulb.
or some low light darker pigmented coral.

if you also start seeding your tank with scrapings of other tanks Coraline. you will introduce more genetic variation within the pigmentations. this allows for the Coraline that does suit your lighting to take hold... then its like a weed... add calcium, strontium, iodine. etc.

one of the best lights is fiji purple and atinic, it will boost your coraline growth once you have your other chemicals under control.

[ColinD]

Magnesium levels high? When I went on a Bryopsis mission and raise my Mag. to 1600 most of my coralline turned white. Now that my levels are back down to around 1350-1400 my coralline has coloured back up and is starting to cover my rock and glass again.

Colin

[Skimmerking]

bleaching usually caused by to bright of a Kelvin lie 10K or 6500K will cause it to bleach. water level drops and causes the Coraline to be killed from Air. stable PH conditions will grow Coraline.

[paddyob]

I am using a 10k and standard actinic and my tank could not have more coraline if I wanted it to.

As long as bulbs are good and suited for saltwater/reef.... should not matter brand.


Here is a shot from my tank.... all my rocks look like this and I barely dose anything.... calcium once a month (maybe... and kh i throw in my top up pail.

[DiverDude]

My lights haven't changed and the bleaching has been in the last month (bulbs are only ~4 months old). So it's not a perceived colour change (i.e. lighting) but an actual one.

Water parameters are:
SG 1.025
Alk 2.5
Ca 420
Mg 1075
No2 0
No3 0
pH 8.2

Now...what I didn't tell you was that there are some 'issues' I'm struggling with in the tank right now but I wanted unbiased opinions before I mentioned these. I have a bad HA problem When I bought the setup from another CanReefer, it has this issue and I was forewarned. After about 2 months of having the tank the HA was gone.

In the 6 weeks, it has come back with a vengance.

The tank is doing VERY well; everything is happy, healthy and growing like mad -especially the HA !

About 4 weeks ago, I put a small Sea Hare in there to combat the HA (I had done this the first time around and it worked well). It spent 2 days cruising the glass (never ate a thing) and then disappeared into the rockwork. Despite tearing half the tank apart, I have not been able to find the damned thing.

So.... I suspect that I have elevated PO4 (which I don't have a test kit for) and NO2/NO3 which test at zero but I suspect it's the HA that's consuming it all. All this despite doing 15% water changes ever 3-5 days for the last 3 weeks !!

Now with the coraline bleaching, I think I've got my proof and tonight I plan to pull as much HA as I can from the tank, tear apart all the rock and find that damned sea hare and then do a 50% water change. Oh, and I've got a borrowed 36 watt UV sterilizer on the tank to see if that will help too ! (1 watt per gallon -think it's enough ? )

Anyone think I should take the Bio-Pellets out of my reactor and replace them with Phosban for a while ?

[Zoaelite]

When you do your water changes do you drop the water level in the main tank right down? I used to do this until my return pump crapped out mid change and my tank sat half full for about 30 mins. Every bit of coraline above the water level died, everything below survived.

[globaldesigns]

Hey Mark,

Firstly you should get your parameters in check, the following are out of whack:

ALK is to low - the acceptable range is 7-12
Ca is high, but not a biggie - 400 is optimal so I wouldn't worry about that
Mg - way too low, acceptable value is 1350 - plus if you Mg is low, most likely your Strontium is also

Before you can really try to figure out what is the cause, you need your tank stable, right now you have many things not in check, and may be causing some of your issues. I personally don't think HA is related to the above, but again you can't really make good decisions when others things are not in check.

In regards to the BioPellets, they are not the cause... But you can remove if you wish. I just think you will be wasting time there, as you need to stabalize things first, so work on those parameters.

As we also discussed, you are looking at band-aid solutions to things like your HA... Instead you need to look at the solution to the overall problem not a quick band-aid to assist, as the original problem will still be there. In regards to HA, I suspected it to be flow, of which you probably don't have enough, especially through the live rock.... Dead areas can be breading grounds for lots of things (Nitrates, etc) and then they leach into the rest of the water column. Try to get good flow through your aquascaping... Believe me I had issues with HA and Cyano, but once I got the good flow, it is now a thing of the past.

Rick

[DiverDude]

No, water covers everything at all times.