If it's a bacteria bloom it will take its course. I'm sure the alk is fine, it's just low to my likings so that's not to say it's wrong. Keep an eye on your livestock and don't make to much of a drastic change. It's really not a good idea to have that mandarin and even dosing the liquids that say pods isn't enough. They consume more than you can realize just to stay alive. It can take several months for them to starve. I've had mine over 3 years now but it eats everything. I'll never buy another again after this one though.