Cargo trailer gray water tank mounting

[TNGW1500SE]

I just bought a 12' cargo trailer. I have a Transit van with a bed but no bathroom or shower. My plan is to use the front of the cargo trailer to install a shower and a sink and two motorcycles in the back. No toilet is needed because I have a porta-potty. I'm looking to install a 20 gal (or so) tank under the floor to catch the gray water. Any advice on what's a good tank and how to mount it? There's 24" between the frame support that run from side to side.

[ktmrfs]

I was able to mount two 20 gallon grey tanks, plumbed together under my 14' cargo trailer. Depth is a big limit, so that's why I needed side by side tanks. Measured dimensions I could work with then did searches for tanks.
As mentioned getting a vent tube up through the roof was problematic. I had built a shower stall/porta potty enclosure and ran the vent tube up through an edge of that enclosure.

never have come close to filling the full 40 gallons. 2 gallons for a shower at most, 2 gallons for dishes, can take a while to fill the grey tank.

[toddb]

I put 3 class a custom tanks on my trailer, they fit nice between the frame rails. Getting the vent up was the most problematic issue for me, I used 1.5" angle iron and welded up frames for them. 2x20gal for fresh and a 20 for grey, it's additional storage for my truck camper.

[Sjm9911]

Might be easier to add just a drain line and get like 3 aqutainers. 20 gallons for a grey water tank is small. Especially if you have a shower. Its doable, but probably not practical.

[Lwiddis]

Utility trailers are sometimes low on ground clearance. Be strategic on where you place it. The one you are looking at is 8.5 inches in height.

[TNGW1500SE]

This is what I'm looking at:
https://smile.amazon.com/gp/product/B07LBB4RTF/ref=ox_sc_saved_title_10?smid=ANNYFJC2Y5PU4&psc=1

I guess there should be some kind of rubber on the straps?

[agesilaus]

RV water tanks

Tanks are generally held in by metal straps