RO/DI Filters

Morning everyone,

I have a Coralife 5692 Pure-Flo II RO/DI unit. I've been trying to find out which filters are which and for the life of me I can't. Does anyone have an idea of which are which? I'm thinking the one on the top is the pre-filter.

Also are all the replacement filters the same for different manufactures?



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    RO UNIT.jpg
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The top cartridge is for the RO membrane. The vertical cartridges are the pre-filters.

1.Water goes through the pre-filter cartridges first.
2. Then through the RO membrane.
3. Then through the DI cartridge.

Most of the refillable pre-filter canisters have a standard size. Usually 5" or 10" diameter. Then there are the oversized industrial sizes which is not typical in a household setting.
There may be exceptions though, so double check before you buy replacement parts.

I have also seen some RO units for drinking water with non-refillable cartridges and those might have proprietary sizes.