Compare the complete CristalProfi model, pad designation and filtration grade. Select F15 or F35 only when the stated filter assignment matches the existing unit.
Choose JBL UniClear pads for the correct external-filter model
JBL UniClear filter pads in this category are replacement media for specific CristalProfi external filters. The available F15 and F35 versions and the different filter-size assignments must be matched to the exact filter model; the numerical designation alone is not sufficient.
Check the complete model name on the filter and compare it with the compatibility information on the product page. Pads intended for CristalProfi 120/250 are not automatically suitable for the 500 model. Also distinguish between the available pad grades because they may be intended for different filtration stages.
Replace or clean the pads according to the filter and product instructions. Preserve the biological stability of the aquarium by avoiding unnecessary simultaneous replacement of all filter media and by restarting the filter promptly after maintenance.