# Mixing salt - best method of measuring salt & water?

#### Terry

##### Valued Member
Hi. Haven't received my tank & equipment yet (soon hopefully) but how are you Saltwater folks measuring your salt & water to get the right amount of each? For example, the instructions for Red Sea Coral Salt are:

"One level cup of salt produces exactly 3.75 US gallons of seawater solution at a specific gravity of 1.021"

A level cup measurement I can figure out, but how do you calculate the volume of 3.75 gallons in a bucket? Do you use the specific gravity of water (8.33 lbs./gallon) x the gallons you want and weigh that much in a bucket on a bathroom scale? (3.75 x 8.33 = 31.2 lbs. water)

I need to add about 4.9 lbs of the above salt on my initial tank filling (34 gallons), but after that I need to also get set up for partial water changes using salt/water mixed in a 5 gallon bucket. I know I need to check & adjust the final salinity with a hydrometer or refractometer, but where do I start? I can't see sitting at a bucket all day adding a tablespoon of salt at a time, letting it mix & then checking salinity.

BTW, I already have a powerhead, and heater to hook up in the bucket to help the salt mix in, but it seems like every time I'm close to figuring out how to do things I come up with another question!

Thanks

edit: And about how long do I need to wait in between salt (or pure water) adds, before I take another salinity reading?

(see - neverending questions LOL)

#### atmmachine816

##### Fishlore VIP
Hmm I use red sea salt mix and it says pounds on it I think and I used a scale to measure it. You can calculate 3.75 gallons by adding 3 gallon jugs of water and .75 of one and marking it in your bucket. What I did was divide mine by how much water I want to add and add that much salt. I just approx. it and measure my salinity later with a refractometer (I would advise buying one, much better than a hydrometer, easier to read, clean and maintain). I guess it's sort of just guess and mix but by the time your tank is cycled you should have mixing your salt down. I just add some, move my maxi-jet 600 around a bit, s(ince I got it for free but I don't have the spraybar so I can't use it in my tank yet) to dissolve the salt quicker than leave my mini rio on to finish mixing it up. couple hours later I'll check the salinity and if it's 1.024 then I leave it, if it's 1.02? I add more salt since I usually add less salt than I think since I find it easier to add more salt than water since the salt's easier to store. Once I think it's about right I check 24hrs. later to make sure it's good then I turn the powerhead off and just leave the heater on and let the water sit until I need to change my tank water. I always get my Saltwater ready before a water change.

Don't know if that helped but that's what I do.

#### Terry

##### Valued Member
Thanks. That was helpful. I think the Red Sea salt does have a lb/gal figure too - I got the cup/3.75 gallons from their web site. I'll have the hydrometer first, but will graduate to a refractometer when I recover for all the other costs involved. Good idea on the gallon jugs too, and adding a bit less than recommended to start and inching up on it. Eventually I'll have a system figured out to make it all easier & quicker.

#### atmmachine816

##### Fishlore VIP
O well my mom wasn't about to let me use her cup measures for my salt so I just weighed it. You should figure it out fairly soon. I might try the salt crystals later on, I read that they are supposed to be better but I need to do some more research. Here anything about them?

#### Terry

##### Valued Member
atmmachine said:
O well my mom wasn't about to let me use her cup measures for my salt so I just weighed it.  You should figure it out fairly soon.  I might try the salt crystals later on, I read that they are supposed to be better but I need to do some more research.  Here anything about them?
What did you use to weigh your salt? Haven't read anything about the crystals yet. BTW, my tank should be delivered tomorrow, but I may not get to setting it up till the weekend. At least it will be here to work on when I'm home on vacation next week. If I can get well cured rock locally I've learned that I should have little or no cycle to go through before I can begin adding a few critters.

#### atmmachine816

##### Fishlore VIP
My mom had a little scale that I used. That's good news about the tank. I bought my LR cured and had been setup in a tank for quite awhile from a Saltwater store by me and when I got a test kit two weeks later my tank was fully cycled and could have been even earlier, sure does help.

I'll let you know what I find out about the crystals though might take awhile to research them, busy with school this week no longer spring break :'( I think it was something to provide better living conditions for them, but they are certainly much more expensive than regular synthetic salt though for me it wouldn't be a big deal, gallon water change a week but for you it might get expensive, I don't know.