Page 10 - PDZA Sustainable Aquarium Brochure

ALTERNATIVE FILTRATION— large organic matter from the system which can
DRUM SCREEN FILTRATION result in less dissolved total organic carbon (TOC)
Drum screen filters offer the possibility of a compared to sand media filters. Preliminary data
large savings in energy, water use, and space from a drum filtration and protein skimmer-based
requirements. However, it is imperative that the LSS installed at Toledo Zoo’s aquarium suggests a
overall facility design include careful planning to greatly reduced accumulation of nitrate in the water
accommodate this more innovative technology. body. Theoretically, the low rate of nitrate buildup
could be the result of drum screen filters and protein
For the Pacific Seas Aquarium, drum filtration was skimmers quickly removing organic matter which
selected primarily for achieving energy savings up would otherwise release nitrogenous products
to 40% compared to a traditional sand filtration into the water. Table 2 lists the advantages and
LSS. In addition to potential savings in energy disadvantages.
and water use, drum screen filters quickly remove

Table 2—Pros and Cons of Drum Screen Filters

PROS CONS

• Energy efficiency sensitive to placement and
• Low energy head requirement
design of the facility

• Limited water use in back-spraying • Routine maintenance of moving parts

• Large organic particulate quickly removed • Allows dissolved organics to pass thru

• No backwash recovery required • Insignificant biofiltration

10 AQUARIUM OF THE SUSTAINABLE FUTURE: PUBLIC FACILITIES DESIGNED TO EMBODY CONSERVATION