Can you post of picture of where the leak is? Hard to tell exactly from you word description.
Once we see what you have, we can suggest a better recommendation, many with pics and links to product to buy to do the work. But is all starts with understanding what you are up against if they will work.
If your piping is original or black in color, odds are high it is ABS plastic. There are a few not expensive permeant ways to solvent weld or cement/mesh layer up repair the piping/tanks. We have had several members repair real bad breaks, holes in the waste tanks and drain piping with permeant results.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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