Ahoy and welcome. Perfectly decent choice. It's likely to have an M90 spring fitted. An M100 is the default choice for 1.13J-ish Joules.
I say Joules because unless you're playing CQB indoors, you'll likely be wanting to use 0.28g (minimum 0.25g, maybe even 0.3g or higher if your Specna will lift them and budget allows). Unless your site is still stuck in the 1990s and chronoing on 0.2g, you'll want to chrono on the BB weight that you'll be using, and ideally with the hop set for that. The difference can be significant: I have guns that shoot at 1J with 0.28g, but 1.2J with 0.2g, with the hop set appropriately for each weight.
Did yours come with another spring in the box? If so, it will be an M120, although it may be in an M90 wrapper (with the M90 already fitted). You could cut a few coils off of it and see where that gets you. Cutting them down is easy enough.
Oh, I would echo what @Lozartsaid though - play first, get a baseline, then start modifying. You're at 0.9J just now, which is fine - effective range is more about shot-to-shot consistency than maximum power. I'd also agree that ZCI or AOLS barrels and Maple Leaf rubbers (Macaron bucking and omega nub) are a great combination and will likely bump the muzzle energy up a little. You already have a decent rotary hop unit.