You bought TCCA tablets marketed as “5-7 day slow-release”, but by the third day your free chlorine is at zero and swimmers are complaining about eye irritation. What went wrong? In 90% of the field complaints we investigate, it’s not tablet quality — it’s the environment.
1. How TCCA Dissolution Actually Works
A standard 200g TCCA tablet is a compressed powder disc, 76mm in diameter. When submerged in still water at 25°C, it dissolves layer by layer at approximately 30-40g per 24 hours. That is where the 5-7 day rating comes from: 200g ÷ 35g/day ≈ 5.7 days.
But three variables can multiply the dissolution rate by 3-5×:
2. The 7 Root Causes of Fast Dissolution
| # | Cause | Effect on Rate | Fix |
|---|---|---|---|
| 1 | Water temperature > 30°C | +40% | Reduce tablet count during summer peak |
| 2 | Strong water circulation (jets, waterfall) | +80% | Move tablet to lower-flow zone |
| 3 | Chlorinator vs floater | +100% | Use floater for slower dissolution |
| 4 | pH too low (< 7.0) | +30% | Adjust with sodium bicarbonate |
| 5 | Tablet not fully submerged | +50% | Weight-load the tablet properly |
| 6 | Broken/cracked tablet | +200% | Reject tablets with visible cracks |
| 7 | Sub-standard tablet (<85% chlorine) | +30% mass loss | Verify with COA + third-party test |
3. Real Case: 6-Star Hotel in Dubai (2024)
A Dubai luxury hotel reported their TCCA tablets from another supplier were “gone in 3 days”. Site inspection revealed:
- Water temperature: 34°C (pool heated to compensate for AC-cooled air)
- Jet stream directly hitting the chlorinator basket
- pH: 6.8 (below recommended)
- Tablets had visible surface cracks (poor tablet-press process at supplier)
After switching to Shilan Chemical’s 200g crack-free tablets and moving the floater to a still corner, dissolution time returned to 5.5 days.
4. How to Test Your Tablet Quality
Simple field test at your warehouse:
- Place one 200g tablet in a mesh bag at the bottom of a 100L still tank at 25°C
- Weigh remaining tablet at 24, 48, 72, 96 hours
- Expected residual weight: 165g / 130g / 95g / 60g
- If dissolved > 20% faster: reject batch or renegotiate
5. FAQ
Q: Can I make TCCA dissolve slower by pressing harder?
A: No — over-compression cracks the tablet, causing faster dissolution. Optimal press pressure is 30-40 MPa.
Q: Are 200g tablets always better than 20g tablets?
A: For pools > 20 m3 yes; smaller pools should use 20g tablets to avoid overdose and preserve tablet mass.
Q: Should I supplement with cyanuric acid?
A: TCCA already contains cyanuric acid stabilizer. Additional CYA is not needed unless CYA level drops below 30 mg/L.
Buy TCCA That Actually Lasts 7 Days
Shilan Chemical presses TCCA tablets at 35 MPa, uses controlled moisture (< 2%), and pass 24/48/72h dissolution QC on every batch. See our TCCA product line →