what could be causing burning tips

asylumdown · #1 02-10-2014, 09:52 PM

Most of my SPS is doing stellar, but I've got a couple of pieces that have shut down growth over the past couple of months, and I noticed today that a couple of them have what appears to be burnt tips.

Parameters:
Calcium - between 390-400ppm
alk - 8.3
mag - 1400

No idea oh phosphate and nitrate. I run pellets and GFO, and the tests always come out 0.

I dealt with a bout of cyano a while back and dosed with chemo-clean, after that I got SUPER aggressive with GFO changes and started dosing MB7. The bacterial production in my BP reactor basically fried it (as detailed in another thread so I won't rehash it here), and I've now got the modified reactor chugging away, but there was a window of about a week where there were no biopellets, and it's efficiency was all over the place from December until a couple of weeks ago.

would fluctuating nutrient levels cause burnt tips on some species? Or assuming my nutrients have just been driven way down low again with the reactor finally working properly, would an alk of 8.3 be high enough to cause tip burning?

LoJack · #2 02-10-2014, 09:56 PM

Burnt tips is almost always alkalinity fluctuation.

Going aggressive with GFO is almost certainly to blame. GFO can have a temporary affect on Alkalinity where it lowers it. There is actually a pretty current thread in the SPS forum of ReefCentral right now that discusses it.

That drop of usually almost 2 dKh, negatively affects SPS. It is recommended to slowly increase the amount of GFO due to the fact that it can strip water so fast of nutrients, which has a negative impact on your corals.

Myka · #3 02-10-2014, 10:24 PM

Ditto what Jack said, that's exactly what I was thinking as I read through your description.

Sent from my Dungeon using mad Ninja Skillz.

asylumdown · #4 02-11-2014, 05:20 AM

Hmmm, I also just switched GFO brands. So once it's happened, what's the best way to arrest the damage? Snip the burnt tips?

asylumdown · #5 02-11-2014, 05:23 AM

Also I'm losing faith in my Hannah checker for alk. It keeps telling me I'm over 8, but if you guys think this is low alk, then do I have a testing problem, or are those GFO related issues super temporary? I've never tested it immediately after changing GFO, I always test before I drain for a water change (and thus before I change GFO) so I can get a sense of where my tank is at after 7-10 days of no human intervention.

LoJack · #6 02-11-2014, 05:32 AM

It has a temporary effect, so depending on when you test, it could definitely be back to normal. Its not low alk that causes the issue, its a rapid fluctuation in alkalinity that the corals have a hard time adapting to.

I personally would snip the burnt tips, I find this to be a faster solution than waiting for the coral to recover and then regrow its tips. I find that freshly cut tips tend to grow fairly quickly.

I also do not like the Hanna checkers. I have phosphate, alkalinity, and calcium but I only use the phosphate tester anymore. I found the others unreliable and had huge fluctuations testing the same water 2 or 3 different times.

I have since switched to ELOS kits and doubt I'll ever use anything else again … so much easier, and I find the results consistent

neoh · #7 02-11-2014, 07:01 AM

enlightening! I didn't know GFO made significant alk swings. This is good to know. Whenever I see my corals acting up, I'll turn my GFO off for a few days. That would be 'splainin it!

Hope it works out for the best, asylum.

Proteus · #8 02-11-2014, 11:59 AM

Overdose of potassium can look like burnt tips

iceman86 · #9 02-11-2014, 12:24 PM

If your running an ulns keep the alk between 7-8 and as stable as possible. I keep mine at 7.5 so it can still move up or down and be fine. I get burnt tips on anything over 8. I recently ran into the same problem not knowing about the gfo lowering your alk and got rtn overnight and then slowly continued for a week.

Myka · #10 02-11-2014, 01:49 PM

Quote:

Originally Posted by asylumdown

Also I'm losing faith in my Hannah checker for alk. It keeps telling me I'm over 8, but if you guys think this is low alk, then do I have a testing problem, or are those GFO related issues super temporary? I've never tested it immediately after changing GFO, I always test before I drain for a water change (and thus before I change GFO) so I can get a sense of where my tank is at after 7-10 days of no human intervention.

Start doing some checking a few hours after changing GFO, a few hours after doing a water change, just before a waterchange, etc. These are good numbers to know about.

As Jack said, it's the fluctuation in alkalinity, not the actual number. Although alkalinity over 8 dKH combined with biopellets can also cause burned tips, RTN, and STN. With biopellets and any other form of carbon dosing (whether you've achieved ULNS or not) you should keep alkalinity between 7-8 dKH if you're keeping SPS.