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Beginner reefer seeking advice

High Tide Aquatics
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There is minimal surface water agitation with the pump, but I also purchased an Jebao slw-3 for extra flow. Right now there’s a lot of diatoms (I think) and other detritus just sitting on the floor.

Salinity is 1.025. Pretty sure it’s correct if tap water is reading 1.000 right? I did have to increase it this past week. 1 week ago it was 1.019 so I raised it by .001 per day
So did you calibrate with distilled/ RODI water to 0 reading or did you use calibration fluid to 35ppt/1.026 readings?
 
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Tap water is rarely 1.000, use RO/DI from a known good system for calibration.
ahh okay yeah I see someone else mentioned that. Shoot my readings might be off then. I'll compare against RODI once I get my hands on some.
 
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BOD
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I've only calibrated with tap water to 1.0000. Is it possible the tap water could be off?
I think you wanna use distilled water for calibration, tap can have sediments in it making calibration efforts in precise. Distilled lets you know there is zero sediments/ additives.


Distilled you can grab a gallon at just about any store.
 
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I think you wanna use distilled water for calibration, tap can have sediments in it making calibration efforts in precise. Distilled lets you know there is zero sediments/ additives.


Distilled you can grab a gallon at just about any store.
Distilled is not guaranteed to be 0 TDS and I wouldn't use it for calibration. It might be fine for top off but you don't know without testing what is in it. You can get RODI from any lfs if you don't have a system yourself yet.
 
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I used to use a refractometer and calibrated with 35ppt solution, but I would have to re-calibrate it more than I would like and therefore didn't really trust it. Also, if you use calibration solution, that can get out of whack over time due to evaporation, so for me that's two things I can't really trust.

I now use a Tropic Marin Hydrometer and there's no need to calibrate as long as you take into consideration any temperature differences. I have a small tank like you, so it's not deep enough for the hydrometer, but I fill a 500ml graduated cylinder with 450ml of tank water, put the hydrometer in the cylinder, spin it to remove any bubbles, then let it to settle to get my salinity measurement. I can get my salinity checked in the same amount of time as the refractometer, if you count the 45-ish wait for the refractometer's automatic temperature compensation, and way faster than if I had to calibrate my refractometer.
 
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BOD
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Distilled is not guaranteed to be 0 TDS and I wouldn't use it for calibration. It might be fine for top off but you don't know without testing what is in it. You can get RODI from any lfs if you don't have a system yourself yet.
I honestly didn't know distilled could not have 0 tds. I tested one type from safeway several months back it read zero tds when I was using it for ato water.

So if i'm understanding you right, am I right in assuming your implying that rodi water is overall more pure than distilled?

I always kinda thought they were about the same, and it was just not practical to apply the distilllation proccess of water at home. Hence people used rodi filters.
 
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BOD
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I used to use a refractometer and calibrated with 35ppt solution, but I would have to re-calibrate it more than I would like and therefore didn't really trust it. Also, if you use calibration solution, that can get out of whack over time due to evaporation, so for me that's two things I can't really trust.

I now use a Tropic Marin Hydrometer and there's no need to calibrate as long as you take into consideration any temperature differences. I have a small tank like you, so it's not deep enough for the hydrometer, but I fill a 500ml graduated cylinder with 450ml of tank water, put the hydrometer in the cylinder, spin it to remove any bubbles, then let it to settle to get my salinity measurement. I can get my salinity checked in the same amount of time as the refractometer, if you count the 45-ish wait for the refractometer's automatic temperature compensation, and way faster than if I had to calibrate my refractometer.

I have a refrac from when I first started out but haven't used anything else since I got the hanna one.
 
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