Sps issues - have tank parms

[t.priscu]

Hi Guys,
Within the last two weeks I have had a lot of sps slowly dying off starting at the base of the coral. Acro's, stags, and montipora are the main corals suffering. From doing some tests at home I could not figure out the issue. I did have a temp swing that took the temp down from 78 to 73 overnight which I gradually brought back up over the course of a day. Maybe this is the issue and it kick started some major die off but the issue is still persisting even though that was over a week ago.

I sent in my water to aquariumwatertesting and here are the results.

03-31-2014 - Main Tank - 1 of 1
Ammonia (NH3-4) Good 0.01 | 0.000 - 0.050 mg/L
Nitrite (NO2) Good 0.014 |0.000 - 0.100 mg/L
Phosphate (PO4) Good 0.02 | 0.000 - 0.250 mg/L
Nitrate (NO3) Good 1.7 | 0.000 - 25.000 mg/L
Silica (Sio2-3) High 0.9 | 0.000 - 0.500 mg/L
Potassium (K) Low 207 | 350.000 - 450.000 mg/L
Ionic Calcium (Ca) Good 250 |100.000 - 300.000 mg/L
Boron (B) NA NA | 3.000 - 6.000 mg/L
Molybdenum (Mo) High 0.3 | 0.000 - 0.120 mg/L
Strontium (Sr) Good 8 | 5.000 - 12.000 mg/L
Magnesium (Mg) High 1413 | 1100.000 - 1400.000 mg/L
Iodine (I) Good 0.03 | 0.030 - 0.090 mg/L
Copper (Cu) Good 0.03 | 0.000 - 0.030 mg/L
Alkalinity (meq/L) Good 3 | 2.500 - 5.000 meq/L
Total Calcium (Ca) Good 405 | 350.000 - 450.000 mg/L
Iron (Fe) NA NA | 0.000 - 0.010 mg/L

(The last column is the range of NSW).

(update)
Used an online calculator to calculate alk of 3 mg/L to DKH of 8.4


Anyways I'd like your guys opinions on if the params above (which have been stable besides the temp) are fine or something jumps out at you as to why my sps seems to be dying at the base.
.

Anyways thanks for your time and help.
Tom

 

[t.priscu]

Further Info .
Here is my reef angel info of current tank stats.

DIspaly tank temp 78.9
frag tank 79.5
Ph 8.08
ORP 411 MV
Salinity 1.024 (little low but enough to cause die off)?

Thanks again

 

[mhucasey]

I think your Potassium levels are to blame. Very low potassium results in the kind of TN you are describing. Slowly bring up the levels to 380-400, no more than 10-20 points per day.

 

[t.priscu]

I think your Potassium levels are to blame. Very low potassium results in the kind of TN you are describing. Slowly bring up the levels to 380-400, no more than 10-20 points per day.

Thanks for the reply
Any product you would recommend for this?

 

[moray23]

brightwell pottassion-p is the most cost effective potassium additive I have found.

 

[Ink]

Use potassium chloride. That value really fears me, and it could be the main problem. I would rise it by 20ppm/daily till 330ppm, then 10ppm/daily.

I would also dose iron, if You already don't do that. Don't try to measure it, it's unuseful because it quickly bind organics and could not be easily detected by tests. A daily dose ranging from 0,005ppm to 0,05ppm is fine and doesn't harms anyone.

 

[mhucasey]

Yes Brightwells potassium is fine and usually readily available at the LFS store . The Salifert potassium test kit is easy to use and inexpensive to do your testing. By Any chance do you use Red Sea salt? I had problems with low levels when I used Red Sea coral pro salt.

 

[t.priscu]

No I just use the reef crystals instant ocean.

Alright I will begin dosing the potassium and hopefully that will improve my issues. It seems that besides the temp swing the potassium could be a legit reason for the TN im having.

I'll also look into the iron dosing.

Thanks for all the help guys.

 

[Ink]

Please give a double check with salifert potassium test, as said is very easy to perform (follow the instruction and overall open reagent 3 bottle before beginning the test and clean well its tip with soft adsorbing paper without closing it until the test is completed).

 

[t.priscu]

The LFS had the red sea potassium additive and test kit. Hopefully this will solve my issue.
Appreciate the help guys!

 

[mhucasey]

The Red Sea test kit is pretty complicated but it does work, use indirect sunlight when performing the final titration to see the color change. The Salifert test kit is so easy in comparison. Good luck, I think that you should see improvement with NSW potassium levels.

 

[Dapg8gt]

Seems like every thread I read about people sending their water to aquarium water testing comes back with an out of the ordinary potassium level.. I would definitely double check that number as I'm sure your going to.. I think this is the third post I've read in as many weeks showing a really low level. Jmo and good luck