More — weekly tests, observations & checks
More — weekly tests, observations & checks
Water balance (LSI) − etching · 0 balanced · + scaling
Bromine ppm · band = target
pH
Total alkalinity ppm
Calcium hardness ppm
Temperature °F
TDS total dissolved solids · ppm
Filter pressure psi · dashed = backwash due
Flow rate gpm · band = required turnover flow up to design flow
Bathers reported per test
Chemicals used
Bromine feeder
Patterns
Record
Newest first. Print gives a clean monthly report for the binder (3-year record); CSV pastes into the Avenue5 log.
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
Every dose the app suggests points at one number. The band is where the water can sit without action; outside the legal limit the vessel closes.
| Test | Target | Legal limit |
|---|---|---|
| Bromine | pool 5 · spa 6 ppmband 4–6 · 4–8 | 2.5–10 · 4–10 |
| pH | 7.4band 7.4–7.6 | 7.2–8.0 |
| Alkalinity | pool 80 · spa 60band 70–100 · 50–80 | none · test weekly |
| Calcium | 300band 250–400 | none · LSI decides |
| Temperature | pool 82 · spa 102 °Fband 78–86 · 100–104 | spa max 104 |
| LSI | 0band 0 to +0.3 | none · protects plaster and heaters |
| TDS | —under fill water + 1,500 | none · drain when high |
Why alkalinity is kept low. Alkalinity is only a pH buffer: the more you carry, the faster CO₂ loss pushes pH up and the more acid you burn. Calcium carries the LSI instead, so alkalinity can sit at 80 in the pool and 60 in the spa. The company sheet's 80–120 is a generic pool figure, not a rule.
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.
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)
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 alkalinity and pH, × 1.35 for CO₂ loss to the air (matches the standard pool calculators). Needs an alkalinity on record — it will not guess one. One dose, circulate 1 h, 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 → 80 pool / 60 spa with sodium bicarb. Broadcast with pump running; retest after 4–6 h. (Dose tab does the math.)
- Calcium next → 300 in both with calcium increaser, pre-dissolved, added slowly. Retest next day.
- pH → aim 7.4 (band 7.4–7.6). Bicarb pushes pH up, so do alkalinity first and retest before sizing pH Minus.
- 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.
Dosing reference — bromine pool & spa
Every amount the app suggests comes from these rates, scaled to the vessel (pool 15,240 gal · spa 630 gal). Per 10,000 gallons:
| To | Use | Amount per 10,000 gal | Notes |
|---|---|---|---|
| Raise alkalinity 10 ppm | Sodium bicarbonate | 1.4 lb (≈ 3 cups) | Broadcast. Raises pH a little. Retest in 6 h. |
| Raise calcium 10 ppm | Calcium chloride (77%) | 1.2 lb (≈ 2 cups) | Bucket of water first — it heats. 24 h to settle. |
| Lower pH 0.2 | pH Minus (sodium bisulfate) | ~1 lb at TA 80 (more at higher TA) | The app sizes this from your alkalinity — test it first. One dose, circulate 1 h, retest pH. Consumes alkalinity. |
| Raise pH 0.2 | pH Up (soda ash) | ~6 oz | Raises alkalinity too. Fix low TA with bicarb first. |
| Raise bromine 1 ppm | Bromine tablets in the feeder | ≈ 1 tab per 8 ppm | Slow — days, not hours. This is the normal daily sanitizer. The feeder dial sets the rate. |
| Raise bromine 1 ppm now (shock) | Liquid chlorine 10% | 4.8 fl oz per ppm on the bromine scale | Chlorine in a bromine pool does not make a "chlorine pool": it oxidizes the bromide reserve back into active bromine, so it reads on the bromine scale ×2.25. 10.7 fl oz raises 2.25 ppm bromine. Pushes pH up — retest. |
| Shock (alternative) | Cal-hypo (Re-Fresh 59.5%) | 2.2 oz per 2.25 ppm bromine | Adds calcium each time. Never near the tablets. Prefer liquid chlorine here. |
| Lower bromine 1 ppm | Thio-Trine | 1 oz | Half at a time; easy to overshoot to zero. |
Order of operations: alkalinity → calcium → pH → sanitizer → check LSI. One product at a time; retest between. Settling times the app enforces: pH Minus / pH Up 1 h · liquid chlorine 2 h · bicarb 6 h · calcium 24 h · tablets and feeder-dial changes 2 days.
Dilution: a pool backwash replaces about 345 gallons per inch the level drops (554 sq ft). Seattle fill water is ~25 ppm alkalinity, ~20 ppm calcium, 0 bromine — so every inch of backwash lowers alkalinity and calcium by about 2% and the next test will read a little lower. A spa drain resets everything to fill water: follow the fresh-fill steps below.
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.