Instant Ocean salt check alk

[mike31154]

That's strange. I've been using IO exclusively for years & my alk is always low. I find myself supplementing from time to time. Could be my test kit, but I've tried a few different brands of those & the results invariably come out low.

EDIT: I just remembered that a few years ago when starting my system (pre owned) the alk was quite high. I attribute this to the fact that I used treated tap water for the first year or so. Water source (Kalamalka Lake) is quite hard & once I switched to RODI, alk gradually dropped to the low side & has been that way ever since. If you're not using RODI, get some numbers/water report from your water supplier. City/municipal water reports will provide information on TDS levels and most organic & inorganic compounds that make their way to your tap. Alkalinity is usually in there somewhere.

[mike31154]

Edit for last post timed out. I wanted to add the water report from Kalamalka Lake to show the numbers. Note the high alkalinity.

North Kalamalka Lake Intake Water Quality 2008
Water System: Greater Vernon Water
Source: Kalamalka Lake
Facility: Kal Lake Pumpstation
Sampling Point: Kal Lake Intake
Date: 7/14/2008
INORGANIC Results (mg/L unless noted)
Aluminum <0.050
Antimony <0.0030
Arsenic <0.0050
Barium 0.027
Boron 0.021
Cadmium <0.00010
Calcium 40.6
Chloride 5.38
Chromium <0.015
Copper <0.0030
Cyanide < 0.01
Fluoride 0.24
Iron <0.20
Lead <0.001
Magnesium 19.8
Manganese <0.0050
Mercury <0.00030
Molybdenum 0.005
Nitrate (as N) 0.069
Nitrite (as N) <0.010
Potassium 5.07
Selenium <0.0050
Sodium 18.4
Sulphate 51
Uranium 0.003
Zinc 0.011
PHYSICAL Results (mg/L unless noted)
Alkalinity (as CaCO3) 152
Colour <5 TCU
Conductivity 409 microS/cm
Hardness (as CaCO3) 183
pH 7.8
Total dissolved solids 238
Turbidity 1.0 NTU
UV Transmittance @254(%) 91%

Not suggesting that there couldn't also be a problem with the odd batch of salt, just trying to show that there could be other factors at play & that RODI water is always your best bet to ensure long term reef health.

[LeanneP]

Hi Mike,
Yes, I was wondering about the water I use as well, but I had replies originally from people in Alberta as well who were getting high readings with the IO salt. The fact that they sent me a new pail would make me think that they must have got a high reading as well when they tested it. I also roll my pail of salt but IO claims that there is no settling during shipping right on the pail. Anyways, I am happy enough with the service. I will always check alk when starting a new pail from now on.
Leanne

[gregzz4]

Leanne, I heard about this too around x-mas 2011 and then experienced it myself
When I used my first bag bought boxing week, my alk was near 16
I mixed the second bag really well before using and it was still hi
I went through a bunch of bags curing rock and the alk dropped between bags 2 and 3, or so
Since then it's been closer to 9
The 6 bags I bought came in 2 boxes, so not much to explain the batches

I'll soon be opening my first bucket bought the same boxing week, so we'll see what happens