How much salt

BradMugs

New member
I've got my new 90 gal set up. It's full of RODI and now I'm ready to add salt to get it ready. I realize I'll need about two bags of salt but how should I add it (it's been years since I've set up a new salt water tank). Can I just dump a bag in and let it go then measure to see where I need to go from there?

Is there a calculator that will help me better estimate how much salt to add based on the RI of what is in the tank? I'd rather sneak up on it quickly than to go over and have to try to delute - again a calculator would be helpful.

Thanks
 
How much does the bag say? if it's a 50 lb bag. I'd put in just 1 bag first and let everything dissolve. And add probably 5 cups from the other bag and let it dissolve then go from there reducing the amount you are adding the closer you get to the desired salinity. Of course you measure salinity before you add more salt.
 
OK, that's one way - I was wondering if there was a calculator (I thought I saw one for this but maybe not) that would say to add X units of salt that would equal Y gallons mixed. The salt I'm using mixes 1 cup to a gallon of water. With the sump and other water holding goodies I'm not quite sure how much water I have so I though a calculator would help me guess better.

Thanks
 
hmm i am just starting to do a massive mixture too. 180 gal. so far i have used 1 whole bucket of reef crystals. still at like 1.014. maybe another half bucket to get to it right?
 
well if you have a scale, i found that 5 gallons with 725 grams of instant ocean make almost a perfect 35ppt every time.
 
usually a 1/2 cup per gallon will do, it will get you around the 1.025 mark (make sure to figure in how much rock is in the tank)
 
I usually just add and let it dissolve until I reach the salinity I want. Just like in cooking add a little at a time. Most mixes suggest a cup for every gallon to get a salinity of 1.023 but I make mine at 1.026 so I can't use their scale.
 
What i would do is take out about 5 gallons and mix up about half bag at a time... super salinity with like 2 massive water jets like maxi 1200s in the 5g bucket or sumthing....
i would never mix in the tank itself... i tried it in a 20g and still had salt on the bottom for days...

ps if you got live rock in there it will be toast from the thermal and PH shock... from the salt reaction
 
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OK, that's one way - I was wondering if there was a calculator (I thought I saw one for this but maybe not) that would say to add X units of salt that would equal Y gallons mixed. The salt I'm using mixes 1 cup to a gallon of water. With the sump and other water holding goodies I'm not quite sure how much water I have so I though a calculator would help me guess better.

Thanks


Thats what the Refratometer is for... for testing salinity.. they give you an idea of what to mix on box,bucket,bag but for a true reading you need a good calabrated Refratometer to know for sure where you are..

I hate to even mention a hydrometer...

Also please never get into habit of mixing salt directly into the tank.. i know you done this before.. just a friendly reminder..
 
It depends which salt mix you are using. I use Reef Crystals and ~1/2 a cup per gallon of RODI works for me. As other have said let it mix up after slowly adding salt, then check with your refracto
 
diffrent salt mixes use diffrent amounts of salt. the best way is to add some salt, test with a refractometer and so fourth till you get your desired level.
 
OK, I have a refractometer not a hydrometer. I think I need to re-word my question.

I have a 90 gal tank, plus everything that goes along with it full of water (yes I know not to mix in the tank but I'm trying to save a tank that is leaking so I filled the 90+ and and mixing there). Right now the salinity is not quite where I want it - I under guessed the amount of water and under shot the amount of salt to be on the safe side. There is NOTHING in the tank right now except power heads, heaters and water.

So, is there a calculator out there that will tell me I need to add X amount of salt to raise lets say 130 gal of water up 0.014 - I'm sitting at 1.009. I need to use 1/2 cup of salt per gal to mix to 1.023.
 
Well 1.023 SG is prettly low as well.. shoot for more like 1.025 so when you get evaporation it could go up to 1.026-027.. I would still do the same thing drain off 5 gallons of water mix up 5 gallons with 7-8 cups of salt.. and let it mix with pumps and put back in circulate check with refractometer.. keep doing this till your reading is 1.024-1025 you cannot take out what you put in.. with out changing out water for fresh ro/di.. Time to get out the mad scientist gloves.. :p
 
So, is there a calculator out there that will tell me I need to add X amount of salt to raise lets say 130 gal of water up 0.014 - I'm sitting at 1.009. I need to use 1/2 cup of salt per gal to mix to 1.023.

You can figure our the ratio for your salt mix since you already have taken a salinity reading. Since it is 1.009 right now add a reasonable, measured, amount of salt and take a new reading.

If after adding 1 cup of salt, the salinity is increased by 0.01, you will have your calculator.
 
As others have said, just add salt. Check with refracto.

Add more salt, check again.

Keep adding a little at a time until you get where you need to be. Better to be low on salinity than high. If you overshoot then you need to drain some saltwater out and add RO/DI to dilute it...which is a waste of money.
 
I think the relationship between salt and salinity is pretty linear so if .5 cups raises you by 0.025 then you only need to raise by 0.016. So .5 x 16/25 is .32 cups per gallon to get to 0.025 starting from 0.009.
 
Thanks everyone - I finally gave up on a program and did the ratio thing using my base as 90 gal. I added that much salt and got very close so now I've been added a cup or so about twice a day and go it pretty stable.

It was simpler to go back to the guess and add than find a program to do it for you.

Now to get it seeded and start moving forward.
 
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