Will the Thetford Aqua Magic VI be a Direct Replacement for the Thetford Aqua Magic IV?

Updated 03/23/2026 | Published 12/09/2025

Question:

Is the thetford aqua magic iv a direct replacement for the aqua magic 6 .. toilet flange?

asked by: Martin

Expert Reply:

Hello Martin,

Great question. The Aqua-Magic VI # TH37SE uses the same standard 2-bolt pattern and seal style as the Aqua Magic IV. So from a bolting-it-down standpoint, they’re compatible. The only thing you really need to double-check is the space between your flange and the back wall. The Aqua-Magic VI needs about 7-5/8 inches of clearance, while the older Aqua-Magic IV usually sat a little closer to the wall, around 7-1/4 inches. That means the VI just needs a tiny bit more room behind it. In most RV bathrooms this isn’t a problem at all, but if your old toilet was already snug up against the wall, it’s worth grabbing a quick measurement to be sure. If you can measure from the center of the bolts on your floor flange to the wall behind the toilet, I can confirm for you whether the VI will fit perfectly in your space. I attached an image for reference. Please let me know what measurement you come up with.

What kind of camper is this going in? What was your greatest adventure of 2025? Where did you go, what did you see?

expert reply by: Kate F

Where to Measure Wall to Toilet
(click to enlarge)

Kate F.

12/29/2025

Hey Martin, were you able to measure the distance from your toilet flange to the wall to see if the Aqua-Magic VI fits? Once you have that number, I can help confirm the clearance. Let me know what you find—I’m happy to help.

Cee S.

3/20/2026

@KateF I'm not Martin, but I'm interested in the answer as well. My aqua-magic iv measures 10-1/4" from the center of the bolt to the wall baseboard molding as shown in the image. Will the aqua-magic vi fit in my space? Thanks

Kate F.

3/23/2026

@CeeS Hello Cee. Yes, the Thetford Aqua-Magic VI RV Toilet - Standard Height - Round Bowl - Slow Close - White Polypropylene # TH37SE will work for your set-up. The # TH37SE requires a rough-in measurement that is at least 7-5/8", since yours is measuring 10 1/4", that is plenty of room. What kind of camper is this going in, getting ready for the next big adventure?

Cee S.

3/23/2026

@KateF Thank you for your quick response! This will be used in a Toyota dolphin. In the earlier discussion from last year, it was stated that from the flange to the wall required 7 - 5/8 in, but I was not sure where the edge of the flange was. So just to double check that I am understanding correctly, the 7 - 5/8 in distance requirement is from the bolt to the wall then?