mixing salt?

When mixing instant ocean reef crystals how many cups does it take to get a sg of 1.025 with 5 gallons of ro/di water? The bucket only gives directions to mix a sg of 1.021 which is 2 1/2 cups.

 

try 3 cups total and see where that gets you. i believe that is what i do.

 

Never assume anything with my 5gal WC when mixing I does about 2 cups of salt and mix real well, then add it 1/4 cup at a time until I get close to where I want. Then I let it sit for awhile to dissolve and recheck SG adding a little more salt if needed, but not usually. I then do a final SG check the next day before WC.

 

+1 I use a 30 gallon tub to mix water, and I have a measuring cup that is 2 cups and a bit. 30 heaping measuring cups full of salt gets me to 1.026 ish at 77 degrees. I add more salt, or RODI to compensate if I'm off a bit.

I wish I had a more scientific answer for you, but it's something that you eventually just get the feel for. If you only have a 5 gallon container, maybe stick with the Reef Crystals instructions, and then carefully add extra until you get to your desired specific gravity and track how much extra you had to add.

I'd recommend gettting a good refractometer as well.

 

I think the O.P. is trying to calibrate his Hydrometer by using a set quantity of salt to check its accuracy.This is a very bad idea.It is necesary to calibrate it with someones refractometer (WHICH IS CALIBRATED OF COURSE) or get some calibration fluid to calibrate it.

 

No i am not trying to calibrate my hydrometer with this method vinnyboombatz. That would not be very smart. I just figured with all the big io rc users someone would know how much salt it takes to get to 1.025. I had a thread about switching to tropic marin pro reef but everyone blasted me about how well io rc was but it really confuses me that nobody knows how much of the salt it takes to get 1.025? wow! I think im going to switch maybe then I will know how much it takes to at least get a correct salinity. As far as a refractometer i am in the process of getting one.

 

I know how to get to the correct salinity via my refractometer. The exact measurement isnt known bc i only need to get close to what I want and then I either add a bit more salt or a bit more ro/di water to the bucket.

Been doing it this way for 3 years now.

 

maybe the exact amount that you are looking for cannot be measure by cups....like 3.162455 cups of salt to 5 gallons of water equals 5 gallons of 1.025 salwater. Im sure its not as simple as 3 even cups of salt to 5 gallons of water.

 

whats a good refractometer? Are the ones on ebay worth getting or just cheap crap? Its crazy that a company makes REEF salt but puts directions for a sg of 1.021. Do you happen to know why they do that? I know from what i have read on the last 100 web pages i researched reef water should be 1.025-1.026. If im wrong I sure would like someone to help me understand.

 

Thanks for your help skurious