Chemistry ?'s

[918ReefCpl]

Well this morning got out the handy Mad Reefer Chemistry set and went to work testing the water of the 125 - Found the following results

Water - Initial fill (good 'ole city water) - top off has been w/ RO water, unfortunately the recent 15% water changes were with City Water. Going to subsequent water changes with RO/DI.

Temp 81.5'F
Salt Mix - Regular I/O
Salinity 34 ppt (I/O meter) - 1.029 refractometer
PH 8.2 (API)
Ammonia .25 (API)
Nitrite 0.0 (API)
Nitrate .25 (API)
Phosphate
0.2 (Seachem)
0.25 - 0.5 (Salifert)
Silicate .25 (Salifert)
Calcium 400 (Salifert)
Alkalinity - 3.71 meq/L (Salifert)
10-11 dKH (API)
10.4 dKH (Salifert)
Iodine >0.1 (Salifert)
Iodate <0.03 (Salifert)
Magnesium - 1650 (Salifert)

Interesting thing is that I have never put anything into the system for Magnesium. Why would it be so high?
Had a low Ca value (320) and increased it over a 3 day period w/Kent Turbo Ca. A few weeks ago did a 50 gal water change (tap water) w/ Oceanic salt due to a high Borate buffer level as suggested by a member. None of the fish/coral/inverts seem to be having any issues at this time...

Thoughts???

[Percula9]

I guess the Ammonia is from the tap water. Use R/O water only. The Mag test may be in error, do it again. Was the mag test done with R/O water or tap water. If the tap water is that hard it might give such a high mag reading when mixed with salt. Do a comparison test betwwen tap water and R/O mixed with salt.

[918ReefCpl]

The Mag test was done with water directly from the tank - done twice prior to posting -

[Percula9]

I guess the Mag test was done on Tap mixed with salt.

[Boomer]

The ammonia more than likely came for the salt mix and tap water from the break down of chloramines. That "amines" means ammonia. All alt mixes have some ammonia when made fresh Avg ~ .25 ppm NH3-N.

More than likely the Mg++ is an error in your testing. Tap water usually has very little Mg ++ and no where near the amount you are getting from testing. Get a gallon of distilled water or RO as suggested and make up a batch of salt mix and test the Mg++. If you are not in error it may just be a bag high in Mg++. That Kent Turbo Ca will also have a tad of Mg++ but again no where near what you are getting unless it is a bad batch.

[918ReefCpl]

Just to clarify, the tank has been up and running for 2+months already...Prime was used on initial start up and with each water change. Water changes are aerated overnight w/ IO salt mixed in...This batch of tests were done on existing tank water and last water change was a week ago (18gal).

[tecoral]

Ive always found Oceanic normally has 1300+ Mag, its possible you did get a bucket thats higher but a second test from a different kit or LFS would rule out that your test kit is off. 1600 is high even by Oceanic standards.

[acrylic_300]

I wish my tap water was usable...seems I can't even rinse stuff with it without seeing some Diatoms and Red Slime outbreaks. Took me a while to figure out that it was pushing my Alk up and causing Ca to precipitate also.

I always tend to learn things the hard way though...every person I talked to said to use RO water.

[918ReefCpl]

Got out the handy Chemistry set again this evening and went to work testing the water of the 125- Found the following results

Water - Initial fill (good 'ole city water) - last 18gal water change has been completed with RO/DI (SpectraPureMaxCap90), top off has been w/ RO/DI water - Water change scheduled for this weekend.

Temp - 78.4' F
Salt Mix - Regular I/O [initial fill w/ 50gal Oceanic change in Aug] (Kent was used for last water change) - switching to ReefCrystals/Oceanic Blend
Salinity 1.028 refractometer
PH 8.2 (API)
Ammonia .00 (API)
Nitrite 0.0 (API)
Nitrate 80 (API)
Phosphate
0.5 (Seachem)
0.5 (Salifert)
Silicate .00 (Salifert)
Calcium 375 (Salifert)
Alkalinity - 2.63 meq/L (Salifert)
8-9 dKH (API)
7.4 dKH (Salifert)
Iodine >0.1 (Salifert)
Iodate <0.03 (Salifert)
Magnesium - 1650 (Salifert)
Interesting thing is that I have never put anything into the system for Magnesium. Why would it be so high?

1 cup Kent marine Carbon and 1 cup Kent Phosphate sponge in the OceanClear canister filter (changed Sept 15th)

Just added a bunch of frags from fellow ReefCentral AZFRAG members. THANK-YOU!!!

Trying to give them a good start and not kill anything off....thoughts?

[bertoni]

Oceanic is very high in magnesium, I think, so that might be the issue there. Magnesium isn't consumed very rapidly in most systems, either. Other than that, the numbers seem reasonable, although I'd lower the SG to 1.027 or so.

[davidryder]

Mg will naturally deplete and you will find yourself having to dose it in the future. 2 months is still fairly new. Test it twice monthly you should notice it going down slowly - very slowly. Everything else looks good!