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Join Date: Apr 2006
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Dunno about plumbing spaces in the IP35, but things to also consider:
If you are CRUISING, surely you can jog outside the 3-mile limit and pump the tank out?
Or, stop by pumping stations from time to time?
Options to make your tank larger than it is include adding a urinal (simple and cheap!) or switching to a Lavac head, so you don't need to pump as much water into the system every time you use it.
The usual places to hide a larger holding tank are in the bow, or under a settee.