Acros with "Burning Tips" and STN - Help
 

One of my previously hardy acros is suffering from "Burning?" tips. The tips are turning white over a period of several days and sliming a lot. Another large acro colony has been suffering from STN for several weeks now. I think is has stopped and then it begins again.

My alkalinity is 6.4. Calcium is 420.

Anyone have any suggestions?

for starters I'm pretty sure SPS enjoy alk 7 and up.. Especially if your calcium is at 420, I believe the proper alk should be 8.4(ish) dKH. Here's a chart of the balanced alk and calc values. I'm sure you'll see it from time to time.

Alk meq/L Alk dKH Calcium ppm
0------------0-----------360
0.5----------1.4---------370
1------------2.8---------380
1.5----------4.2---------390
2------------5.6---------400
2.5----------7---------410
3------------8.4---------420
3.5----------9.8---------430
4------------11.2---------440
4.5----------12.6---------450
5------------14---------460
5.5----------15.4---------470
6------------16.8---------480
6.5----------18.2---------490
7------------19.6---------500

I'm sure there could be (and probably are) other things going on but since the only info you provided were Alk and Calc, that's all I had to go on :-) So what else is going on in your talk? What are the other params? Do anything different lately?

Thanks for your reply. I thought my alkalinity was too low, so I had already increased the setting on my dosing pump. I have been traveling on business a lot lately and haven't been able to keep as close an eye on my tank as usual. When I got home today, I ran a set of tests and found my alkalinity lower than normal. I also recently was away for 16 days and when I came back found my alkalinity at 6 and my calcium at 500. I had gotten things under control before I left for this most recent trip.

Thanks again for the feedback. I'll work on bringing the alkalinity up over the next 24-48 hrs.

BTW. Everything else is normal. Nitrates and PO4 negligible. I have an AC3 controlling everything except the 2-part doing pump.

What has your alkalinity been at for the last few months? Where does your doser dose into? Does the dosing flow directly into corals?

I've found my SPS get burned tips when alkalinity is low, and it seems some are much more sensitive than others.

I haven't noticed that, I went for probably 8 months where my alk was always below 3 (don't ask!) and the only negative aspect was almost 0 growth. The only trouble I have with tips is from excessive flow. Increasing alk can't hurt either, just not sure that would do it...

The tips on my Stylo and one birdnest would always burn when my alk fell under 3 dKH. Due to a fault kit I had no idea it was that low! Maybe it was a coincidence...maybe low pH or something instead...

I've never measured pH, so can't offer an opinion. I can't keep stylos at the best of times, so you're one up on me :) My birdsnest has pretty much remained perfect regardless of water chemistry, and the only time it took any damage was when a pump was moved and it got too much flow. Then I lost a few tips to algae. Moving the flow and snipping the tips back fixed everything