Caldera 74148 | 35 sq ft Aventine Spa Filter

The Caldera 74148 filter cartridge is a factory-original replacement for select Caldera Aventine® spas. With 35 square feet of filtration across 185 pleats of heavy-duty polyester, it delivers more efficient filtration and better water clarity — so you spend less time cleaning and more time enjoying your hot tub.

Filtration is what keeps spa water clear and comfortable. Every soak leaves behind body oils, lotions, hair, and fine debris, and the cartridge is what removes all of it before it clouds the water, feeds bacteria, or coats your plumbing. When a filter is worn or clogged, the effects spread everywhere: dull water, higher chemical use, softer jets, and a pump and heater straining against restricted flow.

This is Caldera's compact cartridge, sized for the smaller water volumes of Aventine and Adoration models — and it earns its filtration area through pleat density rather than bulk. Caldera specifies a heavy-duty polyester media built to outlast cheaper alternatives, so the filter holds its performance rather than matting down after a season. Like all Caldera filters, it's made in the USA.