Several times is was reported that the WS2300 has different value for rain_total. The value displayed differs from the value read by mysql2300, log2300 and so on. See this Support Question and this Bug Report.
There is already a patch. that allows to set the offset manually.
However as soon as you reset the rain_total value with minmax2300, you have to adjust the value again.
Description of Patch
minmax2300 should be changed to adjust the offset in the config file automatically.
Installation of Patch
Change History of Patch
Discussion and Comments
Patch is obsolete. minmax2300 needs to be patch to write 000000000000 (4times 000) to 0x043A when resetting rain_total.