CL-30 Captain reported a loss of hydraulic fluid in the right-hand hydraulic system during cruise. While on final approach; the system lost pressure and the flight crew was unable to set the flaps in the full flap position but landed safely.

Narrative

After leveling off at FL410; I performed the cruise check checklist. In addition to the normal items; I learned a habit to scroll through the synoptic system pages and look for abnormal numbers; etc. When I did this; I noticed that the right hydraulic system was down to 6% fluid capacity. A few minutes later the system continued to drop to 4%. I shut off the DCMP (DC Motor Pump); a DC-powered pump that backs up the motor-driven pump; to see if that would stop the loss of fluid. That seemed to stop it as the fluid level stopped dropping.At this point; I was pretty sure that we would soon be getting a Right Side Hydraulic Pressure Low Yellow EICAS message and lose the right-side system; so I asked the FO (First Officer) to open and review the procedure for this with me. We reviewed the procedure and prepared for the possible loss of the RH hydraulic system. I have had a RH hydraulic system failure 2x before in the Challenger 300 aircraft. There are two systems and the RH is the least critical. If you lose the RH hydraulic system; the gear extension is unaffected. Flaps must be lowered using alternate flaps; and will take a lot longer to deploy. Also; you won't have all of the spoilers and reverse thrust on the affected side.When we began our descent into ZZZ; the RH system was still operational and had 2 - 4% fluid left. I asked ZZZ Approach for the longest runway; just in case. While being vectored on downwind for the ILS; way sooner than normal; I slowed the aircraft so that we could lower the flaps. I was expecting the system to go when we lowered the flaps to 10; but was surprised to get the flaps to the second detent; 20; and get the gear down with the RH system still functioning normally. At this point; if I hadn't scrolled through the synoptic pages and seen the hydraulic level; I would not have known there was a problem. At the final approach fix; we intercepted the glideslope and I asked for full flaps; flaps 30. That was when the system lost pressure. 4 or 5 EICAS yellow warnings went off at the same time. Hydraulic pressure low; spoilers INOP; etc.; etc. The flaps also stopped traveling halfway between 20 and 30. I instructed the FO to complete the procedure; which consisted of shutting off the hydraulic shut-off valve; and selected alternate flaps. The flaps did not continue to the full flap position. Fortunately; we knew this might happen and had prepared and briefed for it. I held a little extra speed over the numbers and landed smoothly. We had 12;000 ft. of runway; so I did not attempt to use the LH reversers. I used moderate braking and rolled to the end of the runway. We taxied in to the FBO with no more excitement.I recommend making a scan of the synoptic pages a normal part of the cruise checklist. If we had not done this and noticed that the RH hydraulic fluid was low; we would have been completely surprised when 4 or 5 caution EICAS messages all came on at the same time right after crossing the final approach fix.