Do liquid fertilizers go bad/expire?

hi, I wanted to pour in my liquid fertilizer to my tank today and I noticed that the liquid has some sediment and tiny plant matter-like debris when I poured it into the bottle cap. I then looked closely into the bottle (it's a transparent bottle) and found that at the bottom there are several large sized debris. It also smelled different. I haven't been using it for 2-3 months due to algae. Does this mean I cant use the liquid fertiliser anymore? I live in a tropical country and the bottle is always placed in a non-air conditioned room although it is not exposed to direct sunlight. Does this make a difference?