salt question

[Zibba]

any idea how many pounds of salt are in a cup? i ask because on the 160 gal bucket of salt I got, it say that 1.5 lbs should be used for 5 gallons to give salinity of 1.022. I just want a reference while I'm adding salt to my new tank and then I can fine tune with my hydrometer as I get closer. Thanks.

[rihanssu]

how big is your tank?

[spsick]

half cup per gallon gives you 1.024, that's the formula I have always used.

[wes]

If I were you, I'd take a one gallon milk jug, fill it with water, put that into a bucket and start with about a quarter of a cup, mix that up, see where it gets ya. Also, I think most people keep salinity in their reefs up a bit higher, 1.025 for or so for closer to NSW. I think salt companies suggest 1.022 so they can make their bucket size requirements with less salt. :rolleyes:

[Zibba]

90 gal plus 35-40 gal sump.

yeah I've been reading that most people keep their salinity a bit higher than 1.022, but it's what I read on the salt bucket. (so that would make perfect sense for them to meet their "160" gallon requirement)

[mtfatwork]

half cup per gallon gives you 1.024, that's the formula I have always used.

that is pretty much what I do.

[wes]

that is pretty much what I do.

I've got a bucket of oceanic right now, and a quarter cup gives about 1.021, so a half cup would be WAY too much. I'd just do a trial run of a gallon or two and tweak it from there.

[mtfatwork]

90 gal plus 35-40 gal sump.

yeah I've been reading that most people keep their salinity a bit higher than 1.022, but it's what I read on the salt bucket. (so that would make perfect sense for them to meet their "160" gallon requirement)


Yeah, you really can never get 160 gallons out of a bucket, unless you have a FOWLER, in which case it is fine to run lower salinity.

[johnzillmer]

The 'pounds-per-gallon' and 'cups-per-gallon' vary according to the amount of water absorbed into the salt from ambient humidity, increasing the volume of the salt a little and the weight quite a bit. The Oceanic salt that wes uses might just be nice and dry, which is probably ideal.

[wes]

The 'pounds-per-gallon' and 'cups-per-gallon' vary according to the amount of water absorbed into the salt from ambient humidity, increasing the volume of the salt a little and the weight quite a bit. The Oceanic salt that wes uses might just be nice and dry, which is probably ideal.

I do try to keep that lid on there super tight

[johnzillmer]

I do try to keep that lid on there super tight

Good idea -- this is one reason buckets are way better than bags. I wonder, too, how much of the trace elements and minor elements are affected by excess moisture in the dry salt mix; since, for example, iodine seems to degrade pretty quickly even in a bottle of additive, it must degrade in damp salt mix.