New refractometer ... SG 1.032

[MO Will]

Like the title implies. The refractometer was calibrated with an ultrapure water solution.

How to correct this back to a target of 1.027? The volume of the system is 58 + approximately 80 gallons. So I guess I could siphon out 5 gallons per day and replace with RO water until th problem is corrected.

Thanks in advance for the replies!

[ek9vboi]

Picture this. Your tank has been going on like this for who knows how long. A sudden change can make it crash, etc. Do your regular waterchanges and slowly fix it.

Lets say you do a 10g weekly waterchange. Mix the new batch at 1.027 and it will eventually go down to 1.027.

Could it be that your tank has evaporated so and so amount of water and that could be the reason as to why your tank salinity is o high?

[Myka]

I think you should target 1.025-1.026 personally I think 1.027 is too high.

[Billybeau1]

Mo, I like you already because you are a Cardinals fan.

You see I am a White Sox fan and my wife is a Cubs fan. (Bad Karma)

It works, but anyways, to the problem at hand.

Some, if not most, refractometers cannot be calibrated with ro/di regardless of what the manufacture says.

If one is to get a handle on ones tank parameters, one must know that their instruments are reading accurately.

The best solution is to get yourself some 53ms calibration fluid and (properly) calibrate your refract.

Pinpoint makes a fine 53ms fluid and once you do that, you should be good to go.

I wouldn't make any corrections to your tank until you know your real s.g.

I would target 1.025 - 1.027 if it's a reef. :)

[bertoni]

http://www.reefkeeping.com/issues/2004-06/rhf/index.php

That article explains how to make a DIY calibration solution, which might be useful, too. The PinPoint is nice to have, though.

[MO Will]

OK guys I will get the Pinpoint calibration fluid

I wasn't planning to correct the problem quickly

I replace the evaporation daily with RO and limewater so I don't think it is related to evaporation

I will post back when I get the calibration fluid

Thanks

[MO Will]

I think that the easiest way for me to correct this will be to remove SW and add RO/DI water - maybe a gallon each day

I have an estimated volume of 140 gallons - display plus sump

Is there a calculator or formula that would help me understand how much SW would need to be replaced with RO/DI water??

Thanks

Will

[Aquarist007]

<a href=showthread.php?s=&postid=10072519#post10072519 target=_blank>Originally posted</a> by Myka
I think you should target 1.025-1.026 personally I think 1.027 is too high.
i agree
our preferred rate in this area is 1.024

[bertoni]

I target 1.026-1.027, and have had tanks rise to 1.030 without any problems. SG is fairly flexible, and 1.0264 is the canonical average sea water. I don't see any reason to believe that changes upward are any more (or less) dangerous than shifts downward.

[MO Will]

Thanks for the continued input

Still wondering how much water would have to be changed to get the SG to come down

Ordered the calibration fluid today

Will

[marsh]

MO Will

Still wondering how much water would have to be changed to get the SG to come down


Just because I've had too much coffee today....I hope it is right...

system volume = SV
sg now = sgN
sg desired = sgD

volume to replace with DO/DI to lower sg =

SV -((SV)(sgD-1)/(sgN-1))

For you with a system volume of 80 G sg now = 1.032 and desired sg = 1.026....volume to be replaces = 15 gallons


I wouldn't do anything until the refractometer is calibrated with the correct solution.

[MO Will]

Thanks

I know why I majored in Art History and not math

I just upgraded my sump so SV is 140 gallons or 26 gallons to replace = alot of water!

Thanks

Will

[MO Will]

Ok guys ... Finally got the Pinpoint 53.0 mS calibration fluid. My refractometer was off by 0.002. My swing arm hydrometer was off by 0.005! My current salinity after calibration is 1.028, so I will try to bring it down to 1.026 over the next week or so. I have been removing 2-3 gallons of SW per day and replacing it with RO/DI.

Thanks

[Boomer]

In the future MO

No more than 1 actual unit / week, so it would take you 2 weeks. You are at 1.028 and need to get to 1.026 ie., 1.028-->1.027-->1.026

This will make it easier

http://www.saltyzoo.com/SaltyCalcs/SalinityAdjust.php


Take note that if you use SG in the first two boxes and salinity in the last box (where you have to enter ppt) it will generate a table of 37 columns. Pay no attention to that and just look at the right column where it gives the target SG/ppt you want like 1.026/ 35 ppt.. Example 10 gals, 1.028 to lower to 1.026 and lowering it 1 ppt / WC = 1.026/35.1 ppt = two WC changes not 37 WC.

If you type in SG as above and 1 ppt in the last box
1 1.028 sg / 37.1 ppt 0.3g 1 sg / 0 ppt1.027 sg / 36.1 ppt
2 1.027 sg / 36.1 ppt 0.3g 1 sg / 0 ppt***1.026 sg / 35.1 ppt***
3 Forget this and all lines below .


It is close to take SG and convert it to these and enter these ppt in the windows, which fill not give a table 27 columns long but the proper 2 columns.

1.029 = 38 ppt

1.028 = 37 ppt

1.027 = 36 ppt

1.026 = 35 ppt

1.025 = 34 ppt

1.024 = 33 ppt

1.023 = 32 ppt

[Aquarist007]

<a href=showthread.php?s=&postid=10076068#post10076068 target=_blank>Originally posted</a> by bertoni
I target 1.026-1.027, and have had tanks rise to 1.030 without any problems. SG is fairly flexible, and 1.0264 is the canonical average sea water. I don't see any reason to believe that changes upward are any more (or less) dangerous than shifts downward.

I've been keeping mine consistently .024 since I started the tank--should i raise it to 1.026(slowly)

[Billybeau1]

If you have a reef tank then raising to 1.026 could be beneficial. If it's a fish only, you are fine where you are. :)

[Aquarist007]

<a href=showthread.php?s=&postid=10171485#post10171485 target=_blank>Originally posted</a> by Billybeau1
If you have a reef tank then raising to 1.026 could be beneficial. If it's a fish only, you are fine where you are. :)

it is a reef tank-----how will raising the salt level be more beneficial?

[Billybeau1]

Because NSW averages about 35 ppt or 1.0264

We see no reason not to keep our reef tanks there.

The 2 point higher salinity will also raise your calcium and magnesium as you are adding more salt to get to that s.g. And thats a good thing. :D

[MO Will]

I used the calculator. Two water changes of approximately 4 gallons will get me where I need to be ...

Gallons in system:
Current salinity of system (either SG or ppt is accepted): 37
Target salinity of system (either SG or ppt is accepted): 35
Maximum PPT Change (Enter the maximum change in ppt you want to risk per change): 1
Number of gallons in water change (Change as much as is convienient. The more water the less radical the adjustment. This number is only used when raising salinity):



This plan calls for 2 water changes
Tank Sal. (BEFORE) Gallons Salinity Tank Sal. (AFTER)
1 1.028 sg / 37 ppt 3.8 1 sg / 0 ppt 1.027 sg / 36 ppt
2 1.027 sg / 36 ppt 3.9 1 sg / 0 ppt 1.026 sg / 35 ppt

[Boomer]

Yes :)