Below are answers to common questions about the Fortitude Compact under-sink filtration systems.
Product & Model Questions
What is the difference between the CK and CKS models?
The AS-FC50-CK model uses Carbon/KDF media. The AS-FC50-CKS model uses Carbon/KDF media with added Siliphos anti-scale media.
The CKS model helps inhibit scale and corrosion buildup, while the CK model does not include Siliphos.
What does Siliphos do?
Siliphos media helps inhibit scale and corrosion by forming a protective coating on metal surfaces. It is commonly used in areas with hard water conditions.
Does this system soften water?
No. The Fortitude Compact is a filtration system and does not soften water. The CKS model helps inhibit scale buildup but does not remove hardness minerals.
What is the flow rate of the system?
The system supports flow rates of up to 2.6 gallons per minute (GPM).
Does the system require electricity?
No. The Fortitude Compact operates using water pressure and does not require power.
Filter Replacement & Maintenance
What is the correct replacement filter for my system?
The AS-FC50-CK uses replacement filter AF-FC50-K. The AS-FC50-CKS uses replacement filter AF-FC50-KS.
Always confirm your model number before ordering to ensure compatibility.
How often should I replace the filter?
The filter should be replaced every 10,000 gallons or every 12 months, whichever comes first. High water usage may require earlier replacement.
When should I replace the filter sooner than 12 months?
Replacement may be needed earlier if you notice reduced flow, changes in taste, or odor.
For the AS-FC50-CKS model, the return of scale buildup on fixtures may also indicate the filter should be replaced.
Does the Fortitude Compact need to be flushed before use?
Yes. After installation or filter replacement, run the faucet on the cold-water side for 5 minutes before use.
This helps flush the filter and clear any carbon fines from the system.
Installation & Operating Requirements
Can this system be installed on a hot water line?
No. The Fortitude Compact is designed for installation on a cold-water supply line only. Hot water can damage the tubing and filter.
What are the operating requirements for the Fortitude Compact?
The Fortitude Compact should be installed on a cold-water supply line within the required operating limits:
- Water pressure: 25–75 PSI
- Water temperature: 33°F–105°F
- Cold-water connection only
The system should also be protected from freezing because the filter contains water and may be damaged if frozen.
Troubleshooting
What should I do if water leaks after installation?
Turn off the water supply before inspecting the leak.
If the leak is coming from a threaded connection, apply Teflon tape to the external thread before reconnecting. If the leak is coming from a quick-connect fitting, make sure the hose is fully inserted and seated inside the fitting.
If necessary, contact Customer Support.
Why does black or dark water come out during flushing?
Black or dark water during the first flush is normal. This is caused by carbon fines rinsing from the filter.
Run the faucet on the cold-water side for 5 minutes before use. The water should clear after flushing.
Why doesn’t my TDS reading go down after filtration?
The Fortitude Compact is not designed primarily for TDS reduction. TDS stands for total dissolved solids, which are made up mostly of dissolved minerals and salts.
The Fortitude Compact is designed to reduce certain impurities while keeping beneficial trace elements in the water. If TDS reduction is needed, consider a Premier Series Reverse Osmosis system.
Warranty & Support
What warranty coverage is included?
The Fortitude Compact includes a 1-year manufacturer warranty and lifetime technical support.