Solutions HOCL™ Cistern & Catchment Tank Cleaner™ Monthly Maintenance -100G
Description
Description
Keep Your Cistern and Catchment Tank Cleaner Between Heavy-Duty Shock Treatments
After your initial Shock Treatment resets a dirty cistern or rainwater storage tank, the real challenge is keeping it clean. Without regular upkeep, organic film, slime, and odor-causing residues begin building back up on tank surfaces within weeks. The SolutionsHOCL™ Cistern and Catchment Monthly Maintenance and Light Cleaner is designed specifically for this ongoing care routine. Used once per month, it helps slow the return of organic buildup on cistern and catchment tank surfaces, so your stored water system stays cleaner for longer between heavy-duty Shock Treatments.
Step 2 in the Two-Step Cistern Care System
The SolutionsHOCL™ two-step cistern cleaning system is built around two distinct use cases for the same HOCL-based chemistry:
- Step 1, Shock Treatment: use the Cistern and Catchment Shock Treatment when your tank shows visible slime, heavy organic film, or unpleasant odor. This is the heavy-duty reset that lifts accumulated organic buildup from tank surfaces. Use it as needed, not on a fixed schedule.
- Step 2, Monthly Maintenance: use this Monthly Maintenance and Light Cleaner once per month, after the Shock Treatment, as a routine upkeep dose. At the same 20g per 1,000 gallon rate, the monthly dose helps break down fresh organic residues on tank surfaces before they accumulate into the heavier buildup that requires a full Shock Treatment reset.
Together, these two products create a simple, cost-effective cistern care routine: shock when needed, maintain monthly. Regular monthly maintenance means fewer heavy Shock Treatments over time, saving both time and product cost across the life of your cistern or rainwater storage tank system.
How HOCL-Based Natural Oxidation Technology Works in Monthly Maintenance
This Monthly Maintenance product uses the same NaDCC (sodium dichloroisocyanurate) formula as the Shock Treatment. NaDCC dissolves in cistern water to generate hypochlorous acid (HOCL), an oxidizing compound that breaks down the organic matter responsible for slime, odor, and film accumulation on tank surfaces. In a monthly maintenance dose, HOCL targets the fresh organic residues that accumulate between Shock Treatments, including:
- Proteins from leaf litter, insects, and bird droppings entering rainwater catchment systems
- Fatty acids from environmental runoff and organic debris in stored water
- Amines from decaying organic matter settling in cistern and rainwater tanks
- Sulfur compounds from decomposing natural material that contribute to tank odors
After the reaction, the active ingredient converts primarily into salts and water, leaving no harsh bleach-based chemical residue in your rainwater storage tank.
Ideal For These Cistern and Rainwater Tank Systems
- Homeowners, off-grid properties, and rural farms running cistern or rainwater catchment water storage systems who want a simple monthly tank cleaning routine
- Cistern and catchment tank owners who have completed an initial Shock Treatment and want to maintain cleaner tank surfaces month to month
- Anyone managing a rainwater storage tank system who wants to reduce how often a full heavy-duty Shock Treatment is needed
- Properties with 100G tanks or multiple smaller cisterns up to 5,000 gallons combined that need a cost-effective monthly cistern maintenance cleaner
How to Use the Monthly Maintenance and Light Cleaner - 100G
Directions for monthly cistern and catchment tank maintenance:
- Complete your initial Shock Treatment first. This Monthly Maintenance product is designed to follow the Shock Treatment, not replace it.
- Determine your total tank volume in gallons across the cisterns or rainwater storage tanks you plan to maintain.
- Dose at 20g per 1,000 gallons of tank volume. The full 100G package maintains a single cistern of up to 5,000 gallons or multiple smaller tanks with a combined volume up to 5,000 gallons.
- Add the measured amount directly into tank water or into inflow as the tank fills.
- Allow at least 1 hour of contact time for the formula to work on organic residues on tank surfaces.
- Repeat once per month as a routine maintenance dose. If your tank develops visible slime, heavy organic film, or strong odors between monthly treatments, return to the Shock Treatment for a full heavy-duty reset before resuming monthly maintenance.
Quick Dose Guide - 100G Monthly Maintenance
| Tank Volume | Monthly Dose | Package Used | Notes |
|---|---|---|---|
| 1,000 gallons | 20g | 1/5 of 100G package | Small cistern or single tank |
| 2,500 gallons | 50g | 1/2 of 100G package | Mid-size rainwater storage tank |
| 5,000 gallons | 100g | Full 100G package | Full single monthly use of 100G |
Monthly Maintenance vs Shock Treatment: Choosing the Right Product
| Monthly Maintenance | Shock Treatment | When to Switch | |
|---|---|---|---|
| Use case | Routine monthly upkeep | Heavy-duty reset | |
| Frequency | Once per month | As needed, not monthly | |
| Formula | NaDCC/HOCL based | Same NaDCC/HOCL formula | |
| Dose rate | 20g per 1,000 gallons | 20g per 1,000 gallons | |
| 100G price | $19.97 | $29.97 | |
| 500G price | $49.97 | $59.97 | |
| Switch when? | Tank is already cleaned | Visible slime, film, or odor | Return to Shock then resume Maintenance |
How It Works
When added to water, the formula generates hypochlorous acid (HOCL)—a powerful oxidizing molecule that reacts with organic contaminants such as proteins, fats, and sulfur compounds. This reaction helps lift buildup from surfaces and neutralize odors, leaving your system visibly cleaner.
Important Note
This product is not NSF 60 Certified and not EPA registered.
It is sold as a cistern and catchment tank cleaner, not as a disinfectant or sanitizer.
Safety and Usage Information
Safety and Usage Information
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Made In
Keep Your Cistern and Catchment Tank Cleaner Between Heavy-Duty Shock Treatments
After your initial Shock Treatment resets a dirty cistern or rainwater storage tank, organic film, slime, and odor-causing residues begin building back on tank surfaces within weeks. The SolutionsHOCL™ Cistern and Catchment Monthly Maintenance and Light Cleaner is designed specifically for this ongoing care step. Used once per month, it helps slow the return of organic buildup on cistern and catchment tank surfaces so your stored water system stays cleaner for longer, and you need a full Shock Treatment reset less often.

How HOCL-Based Natural Oxidation Technology Works in Your Monthly Maintenance Routine
Organic compounds commonly found in tanks:
- Proteins (from leaf litter, insects, bird droppings)
- Fatty acids (from environmental runoff)
- Amines (from decaying organic matter)
- Sulfur compounds (from decomposing natural material)
What Happens If Not Maintained:
When these organic compounds are left to accumulate between Shock Treatments, they rebuild as visible slime and organic film on cistern and rainwater storage tank surfaces, contributing to unpleasant odors and discoloration over time. A simple monthly maintenance dose helps slow this process.
Product Benefits:
- Helps break down fresh organic film and residues on tank surfaces before they rebuild into heavier buildup
- Used monthly, helps reduce how often a full heavy-duty Shock Treatment reset is needed
- Part of a simple two-step cistern care system: Shock Treatment for the reset, Monthly Maintenance for the routine
4 Easy Steps to Clean Your Tank
1
COMPLETE YOUR SHOCK TREATMENT FIRST
This Monthly Maintenance product is designed to follow an initial Shock Treatment, not replace it. Start there if your tank has not been shock-treated recently.
2
MEASURE YOUR DOSE
Dose at 20g per 1,000 gallons of total tank volume. Measure from the package and add directly into tank water or into inflow as the tank fills.
3
ALLOW CONTACT TIME
Allow at least 1 hour of contact time for the formula to work on organic residues.
4
REPEAT ONCE PER MONTH
Use this dose once every month as your routine tank maintenance step.

HOCL-Based Monthly Maintenance for Cisterns and Rainwater Catchment Systems
The SolutionsHOCL™ Cistern and Catchment Monthly Maintenance and Light Cleaner uses HOCL-Based Natural Oxidation Technology. NaDCC (sodium dichloroisocyanurate) dissolves in tank water to generate hypochlorous acid (HOCL), an oxidizing compound that breaks down the fresh organic film, slime, and odor-causing residues that accumulate on cistern and catchment tank surfaces each month. After the reaction, the active ingredient converts primarily into salts and water, leaving no harsh bleach-based chemical residue in your rainwater storage tank.
This product is not NSF 60 Certified and is not EPA registered. It is sold as a cistern and catchment water tank cleaner for routine monthly maintenance use only, not as an EPA-registered disinfectant or sanitizer.
Designed for Ongoing Monthly Cistern and Catchment Tank Care
Hypochlorous acid (HOCL) is widely studied for its properties as an oxidizing compound in cleaning and environmental surface applications. Our SolutionsHOCL™ formulas use HOCL chemistry for both the Shock Treatment and this Monthly Maintenance product. Visit our Scientific Studies page to explore published research on hypochlorous acid and its role in cleaning applications.
Our SolutionsHOCL™ products are formulated with eco-conscious ingredients. This product is in the process of being submitted for EPA review, although not yet complete. Please review our full line of tank cleaning products.
Why Tank Cleaners Love It

SolutionsHOCL™ Cleaning Formulas
Our cleaning formulas feature Hypochlorous Acid (HOCL) as a key component. HOCL acts as an oxidizing compound that breaks down organic film, slime, and odor-causing residues through oxidation. This Monthly Maintenance and Light Cleaner uses the same NaDCC-based HOCL chemistry as our Shock Treatment, applied as a routine monthly dose to help slow organic buildup from returning to cistern and catchment tank surfaces between heavy-duty resets. Visit our Scientific Studies page for published research on hypochlorous acid and its role in cleaning applications.
Our SolutionsHOCL™ products are formulated with eco-conscious ingredients. This product is in the process of being submitted for EPA review, although not yet complete. Please review our full line of Home Healthy Cleaning Products.
Frequently Asked Questions
Q: What is HOCL and How Does It Function as a Water Tank Cleaner?
Q: What is HOCL and How Does It Function as a Water Tank Cleaner?
Hypochlorous acid (HOCL) is an oxidizing compound generated when NaDCC (sodium dichloroisocyanurate) dissolves in water. As an oxidizer, HOCL breaks down organic matter including proteins, fatty acids, amines, and sulfur compounds that accumulate as slime and organic film on cistern and catchment tank surfaces. It is widely studied in cleaning and environmental surface applications. This product is not NSF 60 Certified and is not EPA registered; it is sold as a cistern and catchment water tank cleaner for routine monthly maintenance use only.
Q: What exactly is the Cistern and Catchment Monthly Maintenance and Light Cleaner?
Q: What exactly is the Cistern and Catchment Monthly Maintenance and Light Cleaner?
The Cistern and Catchment Monthly Maintenance and Light Cleaner is an HOCL-based cistern and rainwater storage tank cleaner designed for routine monthly use. It uses NaDCC-based HOCL chemistry at 20g per 1,000 gallons and is intended to be used once per month after an initial Shock Treatment to help slow the return of organic film, slime, and odor-causing residues on tank surfaces between heavy-duty cleans. The 100G size covers one monthly dose for up to 5,000 gallons. The 500G value size covers one monthly dose for up to 25,000 gallons.
Q: Is this product safe for drinking water systems?
Q: Is this product safe for drinking water systems?
This product is not NSF 60 Certified and is not EPA registered as a drinking water treatment chemical. It is sold as a cistern and catchment water tank cleaner for routine monthly maintenance of water storage tank surfaces only. Consult applicable local regulations regarding water storage system maintenance requirements for your specific use.
Q: How often should I use the Monthly Maintenance and Light Cleaner?
Q: How often should I use the Monthly Maintenance and Light Cleaner?
Once per month, as a routine cistern and catchment tank maintenance dose. If between monthly treatments your tank develops visible slime, heavy organic film, or a strong odor, that is a signal to use the Shock Treatment for a full reset before returning to the monthly maintenance routine.
Q: Do I need to do a Shock Treatment before using this product?
Q: Do I need to do a Shock Treatment before using this product?
Yes. The Monthly Maintenance and Light Cleaner is designed to follow an initial Shock Treatment, not replace it. Starting monthly maintenance on a tank that has not been shock-treated means the monthly dose is working against existing heavy organic buildup, which it is not designed to handle on its own. Complete the Shock Treatment first, then begin the monthly routine.
Q: Will it damage my tank or plumbing system?
Q: Will it damage my tank or plumbing system?
The Monthly Maintenance and Light Cleaner is designed for use in cistern and catchment water tank systems, including plastic, concrete, and metal tanks. Do not use in ponds, aquariums, or any system with aquatic life. This product is toxic to aquatic organisms. Always follow dosing instructions and store separately from acids, ammonia, and other cleaning chemicals.
Q: Do I need to scrub or rinse my tank after use?
Q: Do I need to scrub or rinse my tank after use?
No scrubbing is required. Add the measured dose directly into tank water or into inflow as the tank fills. Allow at least 1 hour of contact time for the formula to work on organic residues on tank surfaces.
Q: Is it safe for the environment?
Q: Is it safe for the environment?
After the reaction, the active ingredient converts primarily into salts and water, reducing chemical residue in your cistern or catchment tank system. The formula is eco-friendly and septic-friendly. Do not dispose of large quantities into drains or waterways and follow local regulations for product and container disposal.
Q: Will this help reduce odors from my tank?
Q: Will this help reduce odors from my tank?
The Monthly Maintenance and Light Cleaner is designed to help break down odor-causing organic residues that accumulate on cistern and catchment tank surfaces each month, including sulfur compounds, amines, and other organic matter. Used consistently once per month after an initial Shock Treatment, it helps slow the rate at which odor-causing residues rebuild between full heavy-duty Shock Treatments.
Q: Does this product expire?
Q: Does this product expire?
Store in a cool, dry, well-ventilated place below 30 degrees C (86 degrees F), tightly closed and protected from moisture. When stored as directed, the product is typically suitable for extended storage. Check your packaging for best-by or lot information.









