No special tool. The clips which look green or yellow have 2 tabs which are squeezed together with a small channel-lok or similar pliers until the barbs will pass by the groove inside the bulkhead connector which normally retains them against pulling out. Usually you can get one side free then wiggle the hose lots and in the end the other will come free. The overall fit is tight and it took me lots of steady pulling to get them to free up. Even with the barbs past the groove the fit is tight due to sealing rings.

Please pay attention to the order of the rings and spacers and also notice that one or more may remain inside the connector rather than coming out with the hose.