Although S.G. 1.026 is correct, I'm wondering if you have an Auto Top Off (ATO)? As water evaporates, your S.G. will climb and might wonder dangerously high. Also if you don't have a refractometer, that 1.026 may be off, further causing problems. Just to be safe I would run my S.G. at 1.023, especially if you are only going to have fish and softies.