OMNI-Doulton combination

I now have an OMNI 2 micron sediment filter and would like to use it as a prefilter to the Doulton IS100SC. We live in the rain forest of Costa Rica and our well has high sediment content. I know that Doulton sells a dual filter, (the IP200UC+) but I would like to save the $$ if the flow rate will not be compromised by the OMNI-Doulton combination.
The flow rate will not be compromised unless the Omni filter have 1/4 inch tubing. Doulton ceramics are very tight therefore our supply lines are 3/8 inch to increase the pressure. However you may not even need a pre-filter, she just have to clean the cartridge more frequently, perhaps every 2 months. Clean candle have flow rate of about 1/2 gallon per minute. Since she lives in the rain forest (environmentally relatively clean water) all she'll need is IP100SC.