Anybody pumping or draining into a septic system needs to be careful NOT to use the common formaldehyde based RV black water tank treatment.
Formaldehyde based treatment works by killing live active micro organisms. That is good short term in an RV tank which can smell up the RV, and very BAD to kill/disrupt the natural bacterial flora that is doing you a favor by digesting the contents of your septic tank.
Dumping tank contents with formaldehyde frequently can cause more frequent expensive tank pumping, and possibly permantly damage a drain field.
Other biodegradable treatments are available that do not risk these problems.