I haven't done it in a while, and I'm looking to top off my fluids. My res looks a little lower than normal. I feel like I can just unscrew the cap while it's running and top off the fluids. I guess I'm just looking for a few people to reassure me I'm not crazy and to verify I shouldn't have the system off before adding fluid instead etc. I'm thinking having the system running keeps the water moving instead of having problems with it pooling somewhere and overflowing etc. Thanks.