There should be no water coming out of the end of the soaker hose! When you buy a soaker hose, they normally come with a cap that screws on the far end so that water doesn't escape. Not having this cap defeats the fumctioning of the soaker hose as the escaping water mainly goes out the end rather than being forced through the tiny soaker holes. If your hose is missing the cap, any hardware store will have one for sale. (As for the small "plastic disc," I'm not sure what that is unless it's the washer that provides a seal where the hoses join.)