I just checked the salinity and both tanks are at 1.023. what's the best way to raise it?
You can top off with salt water for a while and it will gradually bring your salinity up. Monitor with a refractometer daily until it's 1.025. Do not trust a hyrdometer.
When do you 5G weekly water change, make sure your new water is the same SG as the tank.
I like the top-off idea, so I think that's what I'll do.
I checked the water parameters a little while ago and they are:
ammonia = 0.2
nitrite = below .2
nitrate = below .2
Should I be concerned with the ammonia and nitrate?