High DKH and Alk

[firefish128]

Will a Alk of 4.5 and a DKH of 13.5 cause SPS to RTN.

[plyle02]

Your alk is pushing the limits that high, but should still be ok. Maybe a couple of water changes w/o buffer, should help to bring it down a bit. I would imagine your CA to be a bit high as well. Just make sure that PH, CA, DKH, and MG all within respective levels. IME, RTN has only happened to me with wild caught acropora, and the slightest change in SGA, Temp, and Lighting are what caused mine to RTN. Good luck.

[capn_hylinur]

are you using buffers--its better to find out why that alk is that high before action is taken

[dvanacker]

I think you are confused.....alk is measured in DKH. It is also measured in meq/l and ppm.

So we only need one reading.......are you using two different test kits?

[firefish128]

Thank you for the replies, My tank has been flawless for the last year, i just did a 10% water change, i mixed the SG a little high 1.035, after the water change I tested the water and it was the readings i posted. I'm just trying to figure out if I have A water problem or I have a problem with the corals. The corals that are RTNing are wild Milliporas.

[jmaneyapanda]

Originally posted by firefish128
Thank you for the replies, My tank has been flawless for the last year, i just did a 10% water change, i mixed the SG a little high 1.035, after the water change I tested the water and it was the readings i posted. I'm just trying to figure out if I have A water problem or I have a problem with the corals. The corals that are RTNing are wild Milliporas.

A little high? That is very high.

[firefish128]

Normal seawater I get out of Hillsboro inlet is 1.029

[capn_hylinur]

Originally posted by firefish128
Normal seawater I get out of Hillsboro inlet is 1.029

that doesn't mean the corals are going to tolerate it---ask yourself how many of them in your tank came from that inlet?

Many of the real experts on this site suggest dKh of 10.5 and salinity of .026 for SPS success

[Serioussnaps]

Originally posted by firefish128
Normal seawater I get out of Hillsboro inlet is 1.029

Either testing error, the air is extremely dry which I doubt in Florida or I was right all along that "NSW" varies greatly in salinity from one area to the other. Which one is it?

[kirstenk]

Originally posted by firefish128
Will a Alk of 4.5 and a DKH of 13.5 cause SPS to RTN.

It could. It depends on where your DKH was before the water change. If it was a lot lower then the new DKH is going to stress your corals and you might get some STN/RTN.

Did the RTN start after the W/C or did you W/C because you were seeing some RTN? If it was after the W/C......how soon after?

[firefish128]

Thanks for answering my question kirstenk, i noticed the RTN about 3 days after the w/c. The dkh was around 8-9 and Ca 490 before the w/c. I turned off the calcium reactor and stopped adding make up water for 3 days and levels came down to dkh of 10 and Ca 440.

[GatorWPB]

Originally posted by Serioussnaps
Either testing error, the air is extremely dry which I doubt in Florida or I was right all along that "NSW" varies greatly in salinity from one area to the other. Which one is it?

The LFS I get my NSW from tests at 1.028 and it comes from the Blue Heron (maybe NorthLake) bridge at high tide up here in Palm Beach County. I think it just varies.

[kirstenk]

That swing was definitely large enough to cause coral stress resulting in your RTN and the time frame makes sense. When you get your readings where you want them then start the CaReactor again. If you are not topping off at all, check your SG reading and try to keep it all parameters as stable as possible.

In the future keep your W/C much closer to tank parameters.

Small hiccup.........things should be fine.