Acropora Bleaching

[macman7010]

I have a gold blue tipped Acropora and it has started to bleach from the base up. The coral has been in my tank a little over a month, but just recently the one side of the base is becoming totally bleached.

I was wondering what I could do to get color back. I have the coral in an area of high water flow - the return line from my sump and power head converge where the coral sets ... I thought they liked lots of current but maybe this is too much?

My calcium is 500, and I supplement with Strot, Magnesium, and Iodine plus Kent's Essential Elements. I was wondering what could cause this. The tempature in the tank is aboiut 80 at night but peaks at 83 during daylight hours. Nitrite and Nitrate are 0, as well as ammonia, and ph is 8.3 .

I have the coral in a 50 gallon tank with 10 watts of lighting per gallon, 10000k and 7500 blue actinic. Any ideas?

 

[steve-s]

I was wondering what I could do to get color back. I have the coral in an area of high water flow - the return line from my sump and power head converge where the coral sets ... I thought they liked lots of current but maybe this is too much?

They like very high water flow but it should be all around them without coming from and specific direction. The flow needs to be "caotic" not linear or sustained from a single fided point aimed at them.

My calcium is 500, and I supplement with Strot, Magnesium, and Iodine plus Kent's Essential Elements. I was wondering what could cause this. Nitrite and Nitrate are 0, as well as ammonia, and ph is 8.3 .

Your Ca is quite high and could easily be causing some stress. Additionally the Mg, Sr and Iodine could be poisoning the water; especially if you are not testing for them.

Please post you levels for these as well as the alk. How do you maintain the alk/Ca and if you dose something how often and how much?

The tempature in the tank is aboiut 80 at night but peaks at 83 during daylight hours...I have the coral in a 50 gallon tank with 10 watts of lighting per gallon, 10000k and 7500 blue actinic. Any ideas?

If the lighting where an issue it would most likely be changing color top down instead of bottom up. The temp could be a cause if continually yo-yoing but that would usually cause tissue loss, not bleaching.

Are you sure the coral is simpley losing color and not actual flesh?

Cheers
Steve

 

[macman7010]

Steve,

I dont know, what is actually happening is the orange color is leaving and it leaves behind a bleached color - literally it looks like rugged pieces of bone. I will take a picture this evening and post so you can see what is happening. I havent dosed with Iodine, Mg, or Sr in a while since I do test and the levels have maintained safe without the need for additional dosage.

The tempature bounces day to night - that though I am told is normal in a reef tank because of the intense lighting. I use C-Balance for calcium and alkanity but like the other supplements have not in a while simply because it keeps that balance almost all of the time with little to no shift. My assumption is my aragonite bed keeps the calcium steady.

As far as flow, the best I can do is a sump output, refugium output or powerhead since those are my water flow contributors.

 

[steve-s]

I will take a picture this evening and post so you can see what is happening.

Please do, it may reveal something.

The tempature bounces day to night - that though I am told is normal in a reef tank because of the intense lighting.

Definately not. Constantly fluctuating temps are a large source of stress. Since it is only a 3° swing, you should be able to keep that down with an added fan or two. One blowing the heat away from the lighting and one over the sump. The increased evap will help cool the tank considerabley.

I use C-Balance for calcium and alkanity but like the other supplements have not in a while simply because it keeps that balance almost all of the time with little to no shift. My assumption is my aragonite bed keeps the calcium steady.

I use C-balance as well so I would not suspect that as an issue. I would still be very curious of your alk reading. A Ca of 500 ppm is a concern. Please also post your Mg reading. You need to be very careful of Sr additions, if too high it will interfere with getting an accurate alk reading. Test kits being what they are, the Sr levels will get to a point where the kit cannot tell the ions apart and reports the value of both added together.

As far as flow, the best I can do is a sump output, refugium output or powerhead since those are my water flow contributors.

Nothing wrong with that, you may simpley need to adjust how the water flows. Be sure returns are not directed at anything and if possible towards another return/powerhead to create more turbulance than linear flow.

Cheers
Steve