I would think that Plastic Canvas and Bridal Veil material would suit any project in that tank.
The DIY materials that are
reef safe & invaluable in this hobby are:
- Egg crate flourescent lighting diffuser from Lowes/HD for in-tank shelves and dividers;
- Bridal Veil material in different mesh sizes from the fabric store is excellent for holding filtration media;
- Plastic Canvas used for Needlepoint from the craft store is excellent for pump intake strainers, baskets, dividers, almost anything;
- Gel Superglue, not just for coral fragging but for cementing anything together in-tank;
- Gorilla Glue, for all kinds of in-tank projects including cementing sand & rock to glass (it expands to form a rough surface);
- Marine Epoxy, from Lowes/HD for holding large rocks together;
- PVC pipe from Lowes/HD;
- ABS pipe from Lowes/HD;
- Spa-flex PVC, Vinyl and RV bilge tubing, also fro Lowes/HD;
- Acrylic sheet and rod from Regional Supply;
- electrical parts of any kind for dirt cheap from Ra-Elco company
Have I left anything out? Oh yeah, elastics, zip ties, twist ties, rigid clear plastic packaging, razor blades, hacksaw, and misc tools...

I could go on and on.
I currently use or have used all of the above materials and have most of them in my "fish stuff". I am always happy to share pieces with a fellow hobbyist for free.
Aloha,
Mark

808-345-1049 call/text/visit anytime
P.S.
Remember, the live stuff in the tank(except for fish) does the majority of the filtration. The stuff in the back is just accessory. In small tanks, Macroalgae is just as important, filters the water and looks good too. Coral filter the water - fish pollute.

No external, mechanical filtration, just good water movement.