Live rock bleaching

Ncreefer · Mar 22, 2017

What would cause live rock to bleach overnight? Have not dosed anything. Did do 5 gallon water changes every other day for a week fighting some algae.

wkscott · Mar 22, 2017

Two possibilities that I can think of.
1. Something like an urchin or limpet is eating the coraline algae.
2. Your water parameters, like alkalinity has rapidly changed .

My guess is something is eating it since the loss is very localized. Do you have an urchin?

Ncreefer · Mar 22, 2017

No urchin snails crabs and fish. All corals seem fine good polyp extension. I think magnesium might be low. Thought of that after I posted. Gonna break out salifert kits and test. Thank you for responding

wkscott · Mar 22, 2017

Ncreefer said:
No urchin snails crabs and fish. All corals seem fine good polyp extension. I think magnesium might be low. Thought of that after I posted. Gonna break out salifert kits and test. Thank you for responding

Yes do test alk, ca, and mg., but it still looks like something is munching on that coraline.

CNDReef · Mar 22, 2017

If the coralline was flaking some snails will either eat it or make it come loose. It just happened in my tank and I only have cerith's in it

Ncreefer · Mar 22, 2017

This was overnight and spreading. Margaritas and turbos is all I have

CNDReef · Mar 22, 2017

The picture looks like it was eaten but these reefs have some mysteries to them

Ncreefer · Mar 22, 2017

Yes true magnesium is low 1050. Still testing

0202chunky · Mar 22, 2017

Wow I might have the same problem. I didn't know magnesium could cause this...

Ncreefer · Mar 22, 2017

Well my magnesium is low 1050 and calcium is low at 320

wkscott · Mar 22, 2017

Low calcium would more likely be the csuse over low magnesium. Check your pH also. Low calcium combined with low pH can dissolve coraline algae. This combination affects coraline much faster than it affects hard corals.

0202chunky · Mar 22, 2017

What is a good ph test kit? Brand?

Ncreefer · Mar 22, 2017

I use salifert

0202chunky · Mar 22, 2017

Thank you. Also when your ph is low what do u use to raise it? I hear opening a window is good but what do u suggest?

Ncreefer · Mar 22, 2017

pH is between 8.0 8.3. in past experience. If pH is low alkalinity is low. Raise alkalinity which will raise pH. Correct if wrong please. Just don't raise it too much

0202chunky · Mar 22, 2017

Umm I see. I will check it tonight. Thanks

wkscott · Mar 22, 2017

0202chunky said:
Thank you. Also when your ph is low what do u use to raise it? I hear opening a window is good but what do u suggest?

If your windows have been closed due to cold weather, CO2 builds up in the house and this can lower your pH. You're in SoCal so open those windows up and let in some fresh air.

Soda ash (sodium carbonate), will raise pH rapidly without significantly increasing alkalinity. Do not use baking soda.

wkscott · Mar 22, 2017

Ncreefer said:
pH is between 8.0 8.3. in past experience. If pH is low alkalinity is low. Raise alkalinity which will raise pH. Correct if wrong please. Just don't raise it too much

Although somewhat in sync, pH and alkalinity are independent of each other. This means that you can have a high pH and low alkalinity, and vice versa. This is why it's necessary to test each of these parameters separately.