What if… adjust and watch the balance
What if… adjust and watch the balance
Facility
| Pool | Spa | |
|---|---|---|
| Permit | PR0066659 | PR0066660 |
| Volume | gal · 554 sq ft, 3–5 ft deep (FINAL Pool Data Form) | gal · octagon 7×7 ft, 40 sq ft, 3 ft deep (FINAL form) |
| Sanitizer | BCDMH bromine tabs, CMP PowerClean Tab Ultra feeder | BCDMH bromine tabs, feeder |
| Filter | Hayward S310T sand (2001), Variflow backwash valve | Hayward CX175-ORE cartridge, 175 sq ft — keep a spare |
| Pump | Pentair WhisperFlo (2011) | Recirc WhisperFlo WFE-6 1.5 HP (98 gpm) · jets WFE-12 3 HP (150 gpm) |
| Heater | Raypak C-R266A-EN-X (2018) | Raypak C-R266A-EN-X (Dec 2017) |
| Drains | — | 4 floor drains, Paramount SDX Retro 10" covers on Sta-Rite sumps; Emetron SVRS on both pumps |
| Turnover | 162 min max · 94 gpm design flow (87 dirty) | 6.43 min max · 98 gpm (85 dirty) |
| Test kit | Taylor K-2006 FAS-DPD — bromine 10 mL (1.125 ppm/drop), TA & CH 25 mL (10 ppm/drop) | |
| Health dept | Public Health – Seattle & King County, 206-263-9566 · report injury/illness within 48 h | |
Metropolitan Tower, 1942 Westlake Ave, Seattle · Avenue5 Residential. Full binder scans in the PoolCalculator folder.
Log a chemical addition
Bromine feeder
Maintenance event
Recent additions & events
Water balance (LSI) − etching · 0 balanced · + scaling
Bromine ppm · band = target
pH
Total alkalinity ppm
Calcium hardness ppm
Temperature °F
Patterns
Dosing calculator
Order of operations: alkalinity → calcium → pH → sanitizer → check LSI. Dose in stages, circulate, retest. Never dose off readings taken with bromine over 10 ppm (it distorts pH/TA/CH tests).
LSI calculator
Langelier Saturation Index, computed with the Wojtowicz (2001) revised equation and temperature-dependent constants — the same basis as the Orenda calculator, not the 1964 chart. Negative water dissolves plaster, grout and heater copper; positive water deposits scale. Aim 0 to +0.3.
How LSI is computed (and why it differs from charts)
Settings
Account & sync
Close the facility now if
Any of these is a closure condition under WAC 246-260-131(11) and King County's closure guidance. Close, fix, retest, log the closure and the reopen time. Reinspection fee is 50% of the operating permit.
- Bromine below 2.5 ppm pool / 4.0 ppm spa, or above 10 ppm anywhere (Table 111.1)
- pH below 7.2 or above 8.0 (Table 111.2)
- Spa water above 104 °F
- Main drain or pool bottom not clearly visible (clarity)
- Drain cover broken, missing or loose (entrapment — federal VGB Act + WAC 131(2)(f))
- Recirculation pump, filter or feeder not running — treatment must be continuous 24 h during use
- Feces, vomit, blood, sewage or unknown material in the water — close until cleaned and disinfected
- Barrier gate won't self-close and self-latch — lock it until fixed
Report within 48 hours
Drowning (fatal or not), death, serious injury, or illness associated with the facility: call Public Health Seattle & King County 206-263-9566 within 48 hours and submit the Injury or Illness Report Form (copies in the compliance binder). WAC 246-260-121(1).
Required routine
| When | What | Rule |
|---|---|---|
| Every 24 h | Bromine residual · pH · spa temperature (water over 95 °F) · treatment flow rate · chemicals added · any contamination · drain covers intact · gate latches · clarity · skim floating material | WAC 121(3), 111(4), 131(2) |
| Weekly | Total alkalinity (required). Calcium hardness and TDS (not required — needed for LSI, which protects plaster and both heaters) | WAC 121(3)(a)(iii) |
| Per formula | Drain, clean and refill the spa every ? days = 630 gal ÷ 3 ÷ ? users/day. Last drain: not logged | WAC 131(4) |
| Always | Keep an extra cartridge for the spa filter · keep signage, rules and first-aid kit current · keep these records 3 years and available to the inspector | WAC 131(2)(g), 121(3)–(4) |
Targets vs. legal limits
| Test | Aim (best water) | Legal limit (close if outside) |
|---|---|---|
| Bromine, pool | 4–6 ppm | 2.5 – 10 |
| Bromine, spa | 4–8 ppm | 4.0 – 10 |
| pH | 7.4–7.6 | 7.2 – 8.0 |
| Total alkalinity | 80–120 ppm | no legal range — test weekly |
| Calcium hardness | 200–400 ideal (ANSI/APSP/ICC-11: 150 min, 1,000 max) | no legal range — LSI decides |
| LSI | 0 to +0.3 | no legal range — protects plaster & heaters |
| Spa temperature | 100–104 °F | max 104 |
| TDS | under fill water + 1,500 | no legal range — drain when high |
Sources: WAC 246-260-111, -121, -131 and Appendix A (246-260-999), read Sept 2026. The Avenue5 log sheet's pH 7.2–7.6 is a company target, tighter than the law.
What is verified, what is estimated
| Item | Basis | Status |
|---|---|---|
| Legal limits, routine, closure rules | WAC 246-260-111/121/131 and Appendix A, read Sept 2026 | Verified |
| Volumes | Stamped FINAL Pool Data Forms: 15,240 and 630 gal | Verified |
| Drop conversions | Taylor K-2006 reagent values | Verified |
| LSI | Wojtowicz 2001 revised equation, Plummer & Busenberg constants, Davies activity, ion pairing. Matches the paper's table ±0.02. Two Orenda readings (spa +0.03, pool −0.12, both with TDS blank) are reproduced exactly at an assumed TDS of ~1,300; the 0.03–0.05 gap at our 1,000 default is the blank-TDS assumption, not the equation | Verified |
| Bicarb, calcium doses | Molecular weight and purity | Chemistry |
| pH Minus / pH Up doses | Carbonate-equilibrium model from your TA and pH. Closed-system minimum; CO₂ loss can raise real demand 20–40%, so stage and retest | Model — retest |
| Bromine tablets | ~8 ppm per lb per 10,000 gal (66% available bromine); release rate depends on the feeder | Estimate |
| Shock, Thio-Trine | Product label rates; chlorine × 2.25 on the bromine scale | Label |
| TDS | Assumed 1,000 ppm until you enter a reading | Assumed |
Every calculation has a "?" or "Show the math" next to it. If a number looks off, the math is the first place to look.
Fresh-fill startup (bromine)
Seattle tap water is very soft: alkalinity ~20–30, calcium ~15–25, pH ~7.5–8. Left alone it is aggressive (LSI around −1.5) and will etch plaster and the heaters. Do these in order and log every addition:
- Circulate, test the fill water (Br, pH, TA, CH, temp). Heaters off until step 3 is done.
- Alkalinity first → 90–100 ppm with sodium bicarb. Broadcast with pump running; retest after 4–6 h. (Dose tab does the math.)
- Calcium next → pool 250, spa 200 with calcium increaser, pre-dissolved, added slowly. Retest next day.
- pH → 7.4–7.6. Bicarb pushes pH up; use pH Minus in half doses.
- Sanitizer: load the feeder with tabs, dial high until bromine reaches 4–6 ppm, then back the dial down. A bromine reserve (bromide) builds as tabs dissolve; the first days burn faster than steady state.
- LSI check — once 0 to +0.3, heaters on. Spa to 102–104 °F; re-check LSI hot (temperature raises it).
- Reopen only when bromine, pH, temp and clarity are all inside the legal limits, and log the reopen.
How bromine works here
The feeder dissolves BCDMH tablets, releasing hypobromous acid (the sanitizer). When it kills something it becomes bromide, which sits in the water as a reserve; any oxidizer — the tablets' own chlorine half, or a chlorine shock — turns bromide back into active bromine. That is why chlorine shock in a bromine pool reads on the bromine scale (×2.25) and why the reserve makes dosing steadier over time. Tablets are acidic: expect pH and alkalinity to drift down; bicarb is your main correction. Bromine has no stabilizer, so the indoor location is what protects it — cyanuric acid does nothing for bromine and is not used here.
Test kit (Taylor K-2006 FAS-DPD): bromine on a 10 mL sample, each R-0871 drop = 0.5 ppm chlorine × 2.25 = 1.125 ppm bromine. Alkalinity and calcium on 25 mL samples, each drop = 10 ppm. Combined chlorine has no meaning in a bromine pool — bromamines are still sanitizers — so it is not tracked. Very high bromine (over ~10) bleaches the pH and TA indicators: retest those once bromine is back in range.
Contamination response
Formed stool: close, remove, net/vacuum to waste, raise bromine and hold ≥ 30 min at ≥ 4.5 ppm (2 ppm chlorine-equivalent) with pH ≤ 7.5, filter running; reopen after retest.
Diarrhea or vomit with feces: Cryptosporidium risk — close, remove, then hyperchlorinate (CDC: 20 ppm free chlorine for 12.75 h at pH ≤ 7.5; on the bromine scale that reads ~45 ppm) — call King County first (206-263-9566) because the bromine reserve complicates the math. Filter for the full period, then backwash to waste, neutralize with Thio-Trine, retest everything.
Blood: no closure required if disinfectant is in range; clean deck surfaces. Log every incident (WAC 121(3)(b)(iii)).
Chemical safety
Never mix products. Keep cal-hypo away from anything organic or acidic and away from the bromine tabs (fire risk). Add chemicals to water, never water to chemicals. Never put a chlorine product in the bromine feeder or a bromine tab in a chlorine feeder. Store dry and ventilated, off the floor, labels facing out. Eyewash within reach.
Record
Newest first. Print gives a clean monthly report for the binder (3-year record); CSV pastes into the Avenue5 log.