Hi
FH Fan
To raise the salinty for your gsp, you’ll want to add some salt after each weeks water change...
Basically you want to aim to raise the salinty by 0.002 each week, till you ultimately reach the required salinty of approx 1.022 (when they are an adult)...
Here is a guide for mixing salt water that i saved from before:
Things you'll need (to make life easier):
1) Container at least 3/4 size the total volume of your aquarium.
2) Marine salt
3) Water
4) A measuring cup, plastic or glass preferably (metal corrodes)
5) Hydrometer or Refractometer (refractometer is more expensive but well worth it)
6) Heater
7) Power head of some sort
How to:
1) Fill the container with water equaling 50% of your tank volume
2) Slowly add salt, you have to experiment with how much to add. Each salt manufacturer is different and even then, there is a difference between batches from the same manufacturer.
3) Add heater. (Make sure it is one that can be submerged)
4) Submerge power head and turn it on
5) Make sure all the salt is dissolved in the container. If you see some sitting on the bottom, give it a good stir and check back in a while.
6) Once you do not see any salt in standing on the bottom of the container, let the water mix for a few hours if possible to ensure its really all dissolved.
7) Check Salinty and adjust accordingly.
(Let the water mix over night if needed to ensure all the salt has dissolved.)
8) Do a 50% water change with the new salt water you mixed and put it into the tank and you’ll have brackish water!
The trick is to not raise things more than .002 per week. So, based on a 50% water change, the SG of the first batch of water you mix should be 1.004. Now the question is what is the next one and how do you figure it out? You can use the formula:
(a+b)/2=c.
a= your current SG
b= what you need your next mix to be
c= your target SG
So if your tank is at 1.002 and you want to raise to 1.004 the equation should look like this: (1.002+b)/2=1.004
Hope that helps