You'll likely find that most people like 1.024 - 1.026 and will often swear by the way they do it, but most evidence suggests that anywhere from about 1.022 - 1.028 will work just fine. There is some anecdotal evidence that certain coral won't respond as well to low number likes 1.022 or 1.023 and some others don't like the higher end of the range, but I'm not convinced there's much actual evidence of this beyond personal opinion. Like most things with these tanks the number you choose being consistent is far more important that which number you choose in that range.
My question to you would be, why do you think you're keeping it too low? Are you having trouble with certain corals?