Get a Hanna alk checked and check twice a day. Make sure your alk is rock solid and you should be fine. Almost all issues with keeping sps revolve around alk swings. I expect to keep my alk stable to the tenth and if I get more than two to three tenths swing in 24hrs then I know something is off. Much more than that and things will start to suffer, once you start seeing a full point swing you'll start to lose stuff.