I've been using Thetford with FORMALDEHYDE for forty-plus years.
I currently have two septic systems on my property, and both work fine, even though I, and my friends who keep their rigs here, all use the formaldehyde-based deodorant
. There are eight, regularly used MoHos, Fivers, and TT's here, and they all dump into the same 1500 gallon system as my sister's Mobile Home on the back of the property.
You'll notice that I said deodorant; none of the biotic stuff used for septic systems is in your tank to properly stew. It takes days or weeks to work.
The small amount of formaldehyde is a small price to pay for "Real Freshness"! Could be a good commercial.
I have both systems tested annually, and they're both cooking!
The amount of formaldehyde in a bottle of Thetford's wouldn't faze an ant (IMHO!).
BRING IT ON!
2005 Georgetown 342DS XL, Full Banks Package
2005 Liberty Renegade 4X Toad
1989 Wrangler Sahara Toad
1984 19.5' Beachcraft i/o 5.o liter, 4-bbl (and you thought your Moho sucked gas!)
D/W Carole and Maggie the Teacup Lab (Black Chihuahua)