HDPE, as long as its the regular one without additives such as flame retardants, anti microbial, should be inert. I have had the followings in my tank with NO issues... HDPE, LDPE, PP, PVDF and ECTFE. My issue with PE/PP is that they float.
Great! Can you look at the White Starboard from King Plastics and give me your opinions on that one. This is the one I used below:
White/White King Starboard Plastic Sheets
We offer White/White King Starboard in both established sizes, or cut to your unique requirements. The established sizes offer the most competitive sq/ft price (due to optimized yields), while the cut to size option provides you the opportunity to expedite your project by purchasing material...
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