Gas Tank Leak

[CaptParadise]

1997 Carver 355 aft cabin has auxiliary gas tank located behind bulkhead in aft cabin and under swim platform. Tank started to leak and was emptied in time. This seems to be a recipe for disaster with tank located near stuffing boxes that always leak a little. Moisture caught on tank will cause corrosion.Contacted Carver and they did not advise any widespread problem. Only way to repair is to cut thru swim platform. Also only way to determine exact cause of leak. I do not want to repair if this will be a recurring problem. Any advice?