I hope you are using an algaecide or phosphate remover or that your phosphate levels are naturally very low or that your pool has lots of dilution of water (from backwashing and rain overflow, for example). Otherwise, you may be in for a nasty surprise when your Cyanuric Acid (CYA aka stabilizer or conditioner) rises. The following are chemical facts that are independent of concentration or size of pool:
For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by 7 ppm.
Some simple math shows that even at a low 1 ppm FC per day chlorine usage, Trichlor will add over 100 ppm to CYA in 6 months if there is no water dilution. Higher CYA levels make chlorine proportionately less effective to the point where algae can grow if the FC is less than roughly 5% of the CYA level.