Mixing fritz rpm

[Imee1976]

Hi, I’m brand new and starting my tank tomorrow, I mixed my first batch of salt yesterday. The website says I need 9.8 pounds of salt for 32 gallons at 1.026 sg. I put in half the amount and I got 1.024. I have an RO/DI system. I am using two 950 gph power heads to mix. The water was cold so i put a heater in and brought the temp up to 68 degrees. I’m using a brand new salinity refractometer. Is it possible my refractometer is incorrect?

 

[Flippers4pups]

Hi, I’m brand new and starting my tank tomorrow, I mixed my first batch of salt yesterday. The website says I need 9.8 pounds of salt for 32 gallons at 1.026 sg. I put in half the amount and I got 1.024. I have an RO/DI system. I am using two 950 gph power heads to mix. The water was cold so i put a heater in and brought the temp up to 68 degrees. I’m using a brand new salinity refractometer. Is it possible my refractometer is incorrect?

Has the refractometer been calibrated?

 

[fuelman]

fritz recommends the temp be between 70-75 when mixing. i usually set the controller at 74 then use 1 cup of salt for every 2 gallons of water. typically comes out at 1.026 right on then i raise the temp to 78 to match my tank, mix till clear & add to the tank at that point. but like flippers said you want to check your refractometer with calibration solution every time before testing.

 

[fuelman]

& welcome to R2R!!! i see this is your first post.

 

[Imee1976]

Has the refractometer been calibrated?

I tested it with the RODI water and it was 1. The problem is all our stores are closed until farther notice and can’t get a calibration fluid. I’ll try a small batch in the morning so I can be really Accurate with the measurements and try the refractometer against that.

 

[Imee1976]

So I couldn’t sleep, I measured out 1 litre of water which was 1000 grams and measured exactly what Fritz recommends for 1 litre. i got 1.026 exactly. so i added more salt and the salinity went up. I can only assume the refractometer is working correctly. I think I’m going to start again. I’m using a garbage can to mix and it says 32 gallon and I put exactly 7 cups of fritz salt in it. i Know it’s easy to get one cup wrong either way but not 8 cups.

 

[ocsurferdad]

So I couldn’t sleep, I measured out 1 litre of water which was 1000 grams and measured exactly what Fritz recommends for 1 litre. i got 1.026 exactly. so i added more salt and the salinity went up. I can only assume the refractometer is working correctly. I think I’m going to start again. I’m using a garbage can to mix and it says 32 gallon and I put exactly 7 cups of fritz salt in it. i Know it’s easy to get one cup wrong either way but not 8 cups.

I use fritz rpm and I use it exactly as recommended on the bag 1/2 cup per gallon and I get exactly 1.025-26 every time

 

[Imee1976]

Thanks for the replies. Yeah, I don’t understand what happened but start again to be safe seems to be the better option than just using it.

 

[homer1475]

Trash cans are labeled as "to the top" on the gallonage. So your 32G bin more then likely only has 28 to 29 gallons in it.

 

[Imee1976]

Trash cans are labeled as "to the top" on the gallonage. So your 32G bin more then likely only has 28 to 29 gallons in it.

Thanks that’s good to know. I emptied the can and started refilling it with RO/DI water. Even at 28 gallons I was still 2.5 lbs short.

 

[Imee1976]

So I’ve started from scratch and now the values seem accurate. I have no idea why the first batch read wrong