Looking for some insight or experiences to a situation I'm having with my inground gunite pool with a cartridge filter. Notice the water level seem to be dropping faster than normal about 2 weeks ago when the temperature dropped. At first I figured it was just evaporation but the loss was too quick... I tested yesterday by filling pool halfway up skimmer, then shutting off all equioment until this morning. No noticeable water loss. Turned pump back on this morning and lost half an inch in 3 hours... Also water had been looking more and more cloudy over past 2 days... I put a small bucket over the return jet for about 20 seconds and when I pulled it up I had about a tablespoon of sand/dirt at the bottom... So that explains the cloudiness... Do I have a cracked return line somewhere? What are my options/next steps? Any help is appreciated!