Will the real water reading please stand up?

[jerwin]

Hi GuysI spent some times trying to figure out why my water testing seem to be wrong on my tanks 40 gallon tank. They were high in some area and can not seem to get them down even with a 5 to 10 gallon water change per week. So today I made up fresh saltwater and tested it and got a big surprise. So also went my the local fish store and picked up 2 other brands saltwater and tested it.

My Cal and Mag was high and would not go down. After looking at the readings on instant Ocean I can see why now.

Some things to note. I was using a BRS 6 Stage DELUXE RO/DI System and the local fish store used DI water.

I used the same Hydrometer and the APEX PH Probe (calibrated today)

H=Hanna R=Red Sea S=Salifert A=API X=APEX (Probe)

Fresh Saltwater
Instant Ocean - RO water (Brand I was using)
Salinity = 1.025 (2 Hydrometer tested)
Temp = 79
PH = 8.03(X) 8.3(A)
Cal = 504(H) 435(R) 480(A)
KH = 10(A)
Mag = 1600(R) 1500+(S)
P04= .01(H)
Nitrate = 0(A)
Nittite = 0(A)

Reef Crystals - DI water
Salinity = 1.022 (2 Hydrometer tested, Fish store told me it was 1.025 but I never verified it)
Temp = 79
PH = 8.01(X) 8.2(A)
Cal = 520(H) 300(R) 420(A)
KH = 11(A)
Mag = 1300(R) 1145(S)
P04= .00(H)
Nitrate = 0(A)
Nittite = 0(A)

Tropic Marin Sea salt - DI water
Salinity = 1.022 (2 Hydrometer tested, Fish store told me it was 1.025 but I never verified it)
Temp = 79
PH = 8.03(X) 8.3(A)
Cal = 452(H) 410(R) 400(A)
KH = 7(A)
Mag = 1340(R) 1350(S)
P04= .03(H)
Nitrate = 0(A)
Nittite = 0(A)

After looking at the readings it seems like Tropic Marin is more consistent across the test and when it is low I can raise it up. The only issues is that .03 Phosphate level.

I also have Salinity salt at the house and might pick up a bag of Red Sea salt to test.

Like to hear peoples thoughts on this. I did these test one right after each other with each brand of salt.

 

[jerwin]

So I have had 2 others tell me they have Cal of 600 in their tank from just doing water changes from Instant Ocean. My self and one other are having corals receeding from this I believe.

 

[nrike]

I have the same problem with reef crystals. My fresh water tested very high Ca at 500+ KH at 16+.

 

[AsphaltPays]

Wow what a difference I am gonna have to check mine next time I do a water change

 

[jerwin]

Thanks Nrike

I will test my RO water just to see what i am getting with that. I plan to pick up some Tropic Marin Pro today and do testing on it. I will also get it to the 1.025 when testing. So I will update the thread based on that.

 

[jeffblly]

I don't know why your readings are like that. I just tested rodi water in mixing bucket using reef crystals salt at 1.027 with salifert. Alk Cal mag were a little higher than other brands of salt but just enough to keep up with the corals use. My higher salinity in the bucket probably had an impact on the higher readings as well.

 

[jerwin]

I am not sure either. not sure if it is a batch of salt or what.

I was really trying to point out the really big difference in some of the test kits with different salts. I was always told Instant ocean is a basic salt and much lower in values and a Salt like Trop Marin was higher in values. Based on my reads that is backwards. I will say that the Trop Marin seem to have more consistent readings between the different test. Trop marin was only about a 50 point spread in Cal and almost the same in Mag. Where Instant Ocean was about 70 point spread and the Mag readings were way high. Reef Crystals Cal was worse with almost 220 spread.

 

[Jakef150]

yikes...hope it works out for you

Im using ESV salt. I can control the parameter easily ( it takes time to getting use with it )

Jake

 

[turbo21]

Great test, but the results actually show us absoulutely nothing. Unless we know what test kit has a correct reading the info is pretty useless. just because there is less of a differnece between the test kits with the tm salt doesnt mean anything. i'm not calling you out or disregarding your tests. but without a test kit that we know is close to 100% accuracy those results dont mean anything.

we need someone to pony up some money and send your same samples to aquarium water testing.com and have the results of the three verified with lab grade instrumentation to have the answers we need. but a very great idea

bob