That makes too much of the solution. The cap makes a convenient measuring tool. . . but I've found that you can mark the proper levels on a clear glass or jar for each fill level with a permanent marker or tape and use that.
You can buy a new hose for your Water Pik on Amazon for about $9 but the replacement procedure is a bit complicated, IIRC. Dismantling the tool is not as easy as it should be. I wound up buying a new Water Pik at Costco.
thanks again.suppose after 20 plus years i can sing for a new machine