Odd water chemistty issue

[Kyle Sicard]

Hello,

About 2 1/2 weeks ago my nitrates hit zero via low range red sea test kit. At the time I was dosing 26ml of alk solution, 8ml of calcium solution, and 45 ml of vinegar on a 180g system. The tank was very stable for 2 months so I cut the vinegar dosing down to 20ml to rectify the issue. The nitrates became detectable again but 5 days late they hit zero again so now I'm down to 5ml of vinegar daily. But then after the second time of hitting zero I noticed some of the sps had burnt tips and then the problem started that I have been having recently. My alk and calcium consumption is zero, I had to turn off both my calcium and alk dosers. It's been 3 days since turning them off completely and still the parameters test the same each day. My alk is at 8.12 and I'm trying to get back in the range of 7.2-7.6 but it just doesnt seem to be dropping. Just 2 weeks ago I was dosing almost 30ml of alk solution a day and now it seems that my alk consumption has gone to zero. I'm not really sure what would cause this and I'm trying to be patient and make very slow changes so I would appreciate any advice on why this is happening. I've only lost 2 small frags but im worried if my problems persist for a prolonged period of time I might lose more then just 2 frags.

Currently the alk and calcium dosing pumps are off and I'm just dosing 5ml of vinegar daily to keep the bacteria populations alive. I'm going to continue to test alk daily to make sure something crazy doesnt happen. Hopefully someone can provide some insight on why my alk and calcium consumption has gone hay wire.

 

[Pife]

Sounds like they don't have any nutrients to feed on.

 

[TheEngineer]

Do you monitor your pH? If so, has it dropped?

 

[Randy Holmes-Farley]

With the ongoing vinegar, you may still have nutrients too low.

 

[Kyle Sicard]

Randy would you advise me to completely just cut off the vinegar dosing then? I checked 9 and 5 days ago and my nitrates were 0.5ppm 9 days ago and 5 days ago they rose to .75ppm. I havent checked since due to the nitrates started to rise but I'll check again in a short while to be sure. I'll post back when I check the levels.

 

[Randy Holmes-Farley]

I'd back off more, but the coral issue might have arisen previously and only show now.

 

[Kyle Sicard]

The coral were all very healthy prior to 3 weeks ago. They were encrusting rapidly, colored up, and great PE. They didnt show signs of any issues till the nitrates hit 0 a second time. Some are still colored up but half of them have dulled in color since 2 weeks ago.

I checked my params:
calcium: 450ppm
alkalinity: 7.9-8.0 DKH (tested twice, 1 reading at 7.9 the other at 8.0)
Mg: 1450ppm
Phosphates: 0.05ppm
Nitrates: 0.5 ppm

It looks as if the alkalinity is finally starting to drop. I went ahead and turned off all dosing to let the tank re gain balance on its own. I plan to continue to monitor alk daily and nitrates/calcium 2x a week. I'll leave the dosers off until the demand for cal/alk start to rise again. I'll probably just leave the vinegar doser off until my nitrates get to 5ppm or so again and this time start with really small doses. I've been vinegar dosing for 6 months and I'm not sure why after 4 months of dosing the nitrates just decided to dive bomb to zero. I did notice that my phosphates have really decreased. I'm at 4 weeks on this current GFO batch and usually my phosphates are at 0.12 by now and yet there at 0.05ppm when I haven't changed my feeding schedule at all so maybe something off is happening where the tank is becoming more efficient at reducing nutrients.\, hence the drop in nutrient levels when not much has changed with my husbandry.