Tip necrosis

[Charlie’s Frags]

What causes this?

 

[Flippers4pups]

Are the tips pale with tissue or bone white tissue gone?

 

[Charlie’s Frags]

Brilliant white. Flesh/pigment is gone

 

[Charlie’s Frags]

Just on those tiny tips. The rest of coral looks to be doing great. Good color and nice polyps extension

 

[Graffiti Spot]

Looks like something bumped a branch. I only see one bra ch like that too. Not sure what your seeing.

 

[29bonsaireef]

Any rapid swing in Alk will cause the tips to burn. Too high of PO4 or No3 will weaken tissue as well IME.

 

[Charlie’s Frags]

Phosphate checker 0.00
Phosphorus checker 19 (0.057)
Alk hasn’t moved much in 4 days from 7.9-8.1
What’s weird is that the alk and calcium isn’t being absorbed either. I check everyday and dose accordingly and they haven’t moved in the last 5 days.

 

[jda]

If it just a few, then it could be coincidence.

High alk, along with low, super calcifying N and P values can do this, but you would need to be around .01 or .005 P for this to be an issue and N would have to be more in the range of .01 as well. When this happens, it is very much widespread, so I do not think that this is the issue.

The other probable cause is LED light burn... usually from too high of peaks from some diodes (usually whiteish ones). Acros cannot fight off bad light like other corals can.

 

[BoomCorals]

If it just a few, then it could be coincidence.

High alk, along with low, super calcifying N and P values can do this, but you would need to be around .01 or .005 P for this to be an issue and N would have to be more in the range of .01 as well. When this happens, it is very much widespread, so I do not think that this is the issue.

The other probable cause is LED light burn... usually from too high of peaks from some diodes (usually whiteish ones). Acros cannot fight off bad light like other corals can.

I was thinking myself, this almost looks like “spotlight” related.

 

[Charlie’s Frags]

Hmmmm
Well I did take my whites up 5% last week, so back down they go. These 2 are on exact opposite sides of the tank as well. It’s been a weird tank week. All the sudden they aren’t absorbing any alk or cal but they’re consuming mag and potassium like crazy.

 

[jda]

It still could be total coincidence since the tips higher up are not burnt, but be careful with running LEDs too high over acropora. This is not a quantity thing, but a quality thing... corals that can handle 500+ PAR from a MH or T5 cannot handle it from any LED for long. The vast majority of the LED lit acropora tanks either keep the intensity pretty low, or raise the panels up really high (like 24-36") and crank them up.

Do you have a fish that could be nipping?

 

[Charlie’s Frags]

The only algae eater I have are a bristletooth tang and diamond goby. Light is an AI hydra 52 hd 12” above the water that peaks for 4 hours with blues at 100% white, red and green at 15%, UV at 30% and Violet at 50%. 4 hour ramp up and 4 hour ramp down

 

[SUS]

I’ve been having this same issue too on just a handful of my acros. Burnt tips, no alk or Ca consumption in weeks (stopped dosing and it’s stayed around 7.5). I run halide/t5 combo though. I just figured it was a combo of high light, low nutrients, high alk (was around 9 when dosing).

So I’ve dropped my alk, increased feedings, and raised my light a few inches to see if the problem goes away.

 

[Stigigemla]

Just as in post 7 but i would add that low circulation makes the corals more sensitive. I would test nitrate and if needed raise it to 1 mg/l.
And make a few tests with Hanna to be more familiar with it. You should get very near values if You make a new test directly after the first one.
I would try to hold the phosphourus value around ten.

 

[Rakie]

Hmmmm
Well I did take my whites up 5% last week, so back down they go.

And that's why Alk and Cal isn't being used. Change LED lighting parameters and corals freak out and completely stop taking up alk/cal/trace. I've noticed this in my tank.

Second, making a 5% increase all at once is DRAMATIC and DRASTIC to corals. That's pretty much how people with LED's toast corals. 1% per week MAX, and even that is quick. Also note, for those 5 weeks where you raise 1% your alk/cal/trace uptake may suffer.

LED penetrates deeper than any light source. So high par LED can be especially deadly to corals.

 

[vetteguy53081]

Looks like damage, but could be either high ALK or Bright light burn.

 

[Charlie’s Frags]

Definitely not alk. All stays between 7.5 and 7.8. I test twice a day, everyday