everything i've read says not to use anything like that because it kills beneficial bacteria, not sure if i should use it
found a page about prices
How much does it cost to have the septic tank cleaned out? Prices range from $240 to $300 to pump the tank depending on tank size. There is an additional charge of $10 per foot for reasonable hand digging to expose the tank lids, but this cost can be avoided if you expose the lids yourself. (Never open the septic tank cover - this will be done by a licensed tank cleaner). This equates to just about $100 annually to help maintain the life of your septic system. Prices are subject to change.
Are there any other costs I should be aware of? There can be other per hour and per foot costs associated with the following:
1. Installing risers to bring the tank lid within 12" of the final grade as required by the Technical Standards of the Connecticut Public Health Code effective January 1, 2000.
2. Replacing the outlet filter. Filter cleaning is included in the pumping service, however if the filter is deteriorated or appears to be not functioning a recommendation will be made to replace the filter.
3. Excessive solid buildup. This can occur by not having the tank cleaned regularly and it can take considerably more time to pump and empty the tank. Additional hourly rates apply when dealing with excessive solids.
Should I use a chemical additive to clean my septic tank? No, a septic system is designed to work naturally and without the use of chemical additives. In fact, chemical additives can disrupt the natural biological system within the septic tank and may cause an adverse effect on groundwater. The State of Connecticut and local health department literature on septic systems make specific statements about NOT using commercial chemical additives to clean your septic tank.