SPS Bleached

[Aquattro]

Originally Posted by daniella3d

How come your alkalinity is so high? Are you dosing something for alkalinity? what type of salt are you using?

You just have to keep in mind that with very low level of nutriment it is a risk to have RTN or STN when you have such high alkalinity. It is not safe to keep your alkalinity so high.

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It's high just for fun, as far as I can tell. It's always been high. I even run zeo and have very little nutrient. I supplement with a Ca reactor and use RBS salt. It's been like that for 16 months, so I'm not too worried about the perceived dangers of high alk. I did read on the Internet that it's bad, but you can't believe everything on the Internet. Nasty place, that Internet.
Only RTN I've had was yesterday, and that probably had a lot to do with the frag falling into my torch coral

[Myka]

Your tank is still in its infant days and so are you as far as reef keeping goes, so losing some SPS (especially stag-type) isn't unlikely. I think you should focus on the fact that you're able to keep Monti cap so far, and be happy about that achievement. Going from Montis to Birdnest would probably be a better way to progress rather than jumping straight to stags.

Btw, your nutrients are undetectable, but it depends on what type of test kits you are using. There are more sensitive kits out there particularly for phosphate (Elos has one, D-D Merck has one). What kits are you using? Low nutrients is not a problem for SPS, rather a good thing. Ultra low nutrients (aka ULN) could be an issue for some SPS (definitely an issue for LPS and softies) and you actually can starve them, but you would need to be carbon dosing in order to achieve ultra low nutrients.

People commonly keep SPS in tanks with alkalinity ranging from 7-12 dKH, although 8-10 dKH is more common. Brad's a bit "abnormal" (hahahaha) at 14 dKH, but if he says that's where it likes to sit then sometimes it's not worth fighting things. Higher alkalinity has some bonuses, like helping to keep many algae at bay. Keep in mind though that calcium and alkalinity should compliment each other, so if alkalinity is high calcium should be high too. If you check the link in my signature that mentions parameters I posted a chart that explains the appropriate, complimenting levels.

As far as terminology goes, "bleaching" is usually a slow process where a color gets more and more pastel. RTN is rapid tissue necrosis which is something that usually happens overnight, and almost always starts at the base and goes up. If you catch RTN in the middle of the event you will see the skin falling off the coral in little pieces (sometimes fairly big pieces). STN is slow tissue necrosis which happens over several weeks or several months and can start at the base or the tips. You won't see the tissue falling off because it is going so slowly that the tissue just dissolves unnoticed.

[Aquattro]

Originally Posted by daniella3d

But before buying any delicate SPS I would get these value: calcium 420, magnesium 1350, alkalinity 8. Then try to keep this stable and you will be fine.

While I agree that these are wonderful numbers to GROW SPS, I don't think they're required to keep it alive as a freshly introduced frag. Maybe long term, the stress of not growing might tick it off a bit, but not bleach it in a couple of days.

Now, that being said, there's a lot of advantage in maintaining proper growing levels at all times. I would work on that routine before worrying about adding SPS.