Is TPU reef safe?

[cope413]

Hi Randy,

I'd like to 3D print a little "nipple" for a small pump (it goes on the end of the impeller shaft and seats in the housing)

This is the msds for the TPU material I'd like to use. (I can use any color if any specific colorants are problematic)
Not much is given about their specific resin as it's proprietary, but it's my understanding that urethanes (I believe this specific material is polyether based, but there are polyester based TPU materials available as well) should stay polymerized at reef temperatures, and have very good resistance to salt water conditions.

The part weighs less than 1g, so I'd guess there wouldn't be any issues because the amount of any potential toxin would be so miniscule, but I figured I'd check.

Thanks in advance

 

[jason2459]

Sounds reefsafe and also a food source for bacteria. I dont think I would use the blue coloration.


Can you do ABS?

 

[cope413]

I can print ABS (or other rigid filaments that are reefsafe), but I want a flexible material so that the shaft centers itself. It also helps isolate the vibration and quiet it down.

 

[jason2459]

My only concern is having it slowly break down by bacteria.

 

[cope413]

I'd be fine with that. Others have mentioned this as a concern with PLA but I've had a few frag plugs printed in PLA in my tank for over 2 years with no sign of degradation.

I'm really only concerned with toxicity.

 

[Randy Holmes-Farley Verified Community Expert]

I expect it will be fine.

 

[jason2459]

Yep, reefsafe wise I think it will be fine and if anything may help reduce nitrates

 

[jason2459]

FYI, I used a Thermo Plastic a while ago to very effectively drive down nutrients in my tank to battle a severe algae outbreak.

Can google search
Shapelock DIY N/P reducing Pellets or Nuking the tank...

My first 55g tank. About 6 or so months in PO4 leaching out of the dry rock I started with.

Before getting into biopellets or any kind of carbon dosing

A few months later after adding the shapelock