what could be causing burning tips

[Reef Pilot]

Which acros did you get burnt tips on? I haven't had that with alk swings, but have seen that for two other reasons. And it only affected "skinny" acros, like birdsnest, red dragons, and some others.

One is lighting, if acros were moved to an area where the light was too bright too quickly, tips were bleached. Moving them down, or to a partially shaded area solved that.

And the other is leaving them out of the water too long. My frag rack is out of the water during water changes, and if I leave it too long without bathing them occasionally, the tips can be burnt (birdsnest are most vulnerable to this). Also, has happened when I left them on the table too long while fragging. Clipping off the tips helps with faster regrowth.

I run bio pellets, and my alk runs between 7 and 9, most of the time. Fluctuations happen due to doser adjustments and sometimes water changes. Have hit 10 a few times, but mostly it is around 8. SPS is doing very well. The only time (last summer, and fall) that my SPS got hit, is when my phosphates got too high (when I combined sumps). But that again only affected some of them (like the more delicate deepwaters), with slower growth and some color loss. Once the phosphates were down, growth and color returned.