First, no that is not your problem.
2nd WHy are you throging money down the toilet (literally) the chemicals really do not do much for you if anything, clearly NOT worth the money
IF you can go a month without dumping then a biological like RID-EX RV (not a recommendation for that brand or any other brand. but an example of what I'm talking about) may help.. or not. But for the most part all of em are money down the toilet and that's all.
|True story
Fellow RVer had that same (Very slow drain) issue. Finally he got into the tank
When they cut the hole in the floor.. they just dropped the wood into the tank, where it clogged the drain.
He got it out. (they make elbow length or longer "Rubber gloves"_
Rinsed it off
Double bagged it
Sent it to the CEO of the company.