Fluctuating Salinity

[Pvtgloss]

What's up guys. I'm new to the hobby and just set up my first tank. A used max E170 with a eshopps nano sump under it. I finally added sand and rock Sunday night. I mixed the salt for about and hour and pumped it in the tank. I used a power head to mix. I figured since it was a new tank and nothing in it that I could fill it up and whatever that didn't mix well would in the tank. Maybe I was wrong. Every time I check the salinity with a red sea refractometer I get s didn't reading. It was even doing this in the mixing containers. And I figured what wouldn't mix would eventually in the tank. But it's been 48 hours and if I test in the sump, main tank and rear sump I get different readings. Anywhere from 1.022-1.026. And ideas what's going on?

 

[evelio118]

Have you checked the refractometer with calibration fluid?

 

[Pvtgloss]

No. But I did with RODI water. The love was barely below 0.

 

[Pvtgloss]

Line*

 

[evelio118]

Are you cleaning the glass prism after each reading. If saltwater sits there. It may cause incorrect readings on the next test.

 

[Pvtgloss]

Yeah, I wipe down with di and wipe dry. I'm waiting 15 secs to for the temperature to adjust. I'm trying to figure out some way it's user error but I seem to be testing per instructions. I'm stumped.

 

[scardall]

No. But I did with RODI water. The love was barely below 0.

your readings are 1.44ppt off actual reading when you use RO water. If you want accurate readings use a calibration solution instead. good luck

 

[evelio118]

Here are the calibration instructions I found for the Red Sea refractometer:

Calibration
Alignment should always be carried out with the instrument at 22-25°C. Allow the refractometer to stand at this temperature for 30 minutes before alignment.

• Remove the cover from the alignment screw.
• Place a sample of DI water on the glass prism and check the salinity reading as directed above.
• If the reading is not exactly on the zero ppt mark on the scale, adjust the position of the reading by rotating the alignment screw with the screwdriver provided until the reading is zero ppt.
• Replace the cover from the alignment screw

 

[Pvtgloss]

I'm about to toss this thing. I just took 20 samples about for or six from different parts of the tank. Started at 1.022 for two or three test and slowly dropped down to 1.015. All within 30 minutes. Sucks.

 

[vic5hands]

I'm about to toss this thing. I just took 20 samples about for or six from different parts of the tank. Started at 1.022 for two or three test and slowly dropped down to 1.015. All within 30 minutes. Sucks.

Let it run . stop going crazy . You said nothing is in the tank check tomorrow and bring a sample to you LFS

 

[Pvtgloss]

Good advice vic. Thank you

 

[Miami Reef]

I love my Milwaukee salinity tester. Never going back to handheld refractometers again!

Milwaukee MA887 Digital Salinity Refractometer with Automatic Temperature Compensation, Yellow LED, 0 to 50 PSU, +/-2 PSU Accuracy, 1 PSU Resolution (color may vary)

 

[scardall]

Here are the calibration instructions I found for the Red Sea refractometer:

Calibration
Alignment should always be carried out with the instrument at 22-25°C. Allow the refractometer to stand at this temperature for 30 minutes before alignment.

• Remove the cover from the alignment screw.
• Place a sample of DI water on the glass prism and check the salinity reading as directed above.
• If the reading is not exactly on the zero ppt mark on the scale, adjust the position of the reading by rotating the alignment screw with the screwdriver provided until the reading is zero ppt.
• Replace the cover from the alignment screw

RED SEA instructions are NOT correct for proper calibration of any refractometer. ( reading will be off 1.44ppt) You did read these instruction correctly. Your calibration target is 1.026sg not Zero, so why cal. to Zero? bottom line is if you are keeping fish it does not matter. But with coral especially SPS it is. I hope I helped yah.