Hi Herbert
Look in Files, then in Miscellanious and you will find a file named ''Santorin Holding Tanks''. We followed the plans for the tanks. But one recommendation I would make, would be to make them a little narrower, 2 or 3cm would make a difference . Also we did not put in a deck fitting for the pump out, but fitted the pump out connection to the top of the tank. The thinking being, two less holes cut in the deck. So far working fine.
Regards Joe
Regards Joe