Black Water TekBuhlmann ZHL-16C · OC + CCR
Plan deeper. Surface safer.
Two tools for the serious diver. A fast gas calculator in your pocket, and a full multi-gas decompression planner for open and closed circuit, on the same verified Buhlmann engine your Shearwater runs.
The products
Two apps, one engine.
Both products share the same Buhlmann ZHL-16C core, so the numbers agree from the surface check to the full deco plan.
DTS Gas Guru
The everyday gas calculator. Best mix, MOD, narcotic depth, density and blending, fast, offline, in eight languages.
- Best mix for a target depth and narcotic limit
- MOD, EAD, END and gas density at depth
- Gas analysis (ppO2, EAD/END, MODs) and nitrox/trimix blending with real-gas Z-factors
- Open-circuit and CCR loop tools
- Eight languages, fully offline, optional cloud mix-library sync
DTS v3.0 Dive To Survive
The full decompression planner. Open circuit, CCR and SCR, multi-level, stage cylinders, team sign-off and a complete dive log.
- Buhlmann ZHL-16C, 16 compartments, gradient factors
- Open circuit, CCR (fixed setpoint) and SCR with worst-case bailout
- Multi-level profiles, ICAO altitude, surface intervals and repetitive dives
- Stage cylinders, min gas, lost gas and gas density limits
- Tissue graph, CNS/OTU, ICD detection, post-dive debrief and no-fly time
- Shearwater Bluetooth dive-log import and a full dive log
What it does
Everything a tec dive needs.
Real planning features, not a toy. Each one runs from a single shared engine so the whole app stays consistent.
OC, CCR + SCR planning
Open circuit, closed circuit with a full setpoint model (descent, per-level bottom, deco) and semi-closed, with worst-case OC bailout schedules.
Gradient factors
GF Low and GF High control first-stop depth and surfacing conservatism, your call.
Stage cylinders
Per-diver stage and bailout cylinders, selectable per dive, with real cylinder volumes in the gas plan.
Tissue compartments
The full 16-compartment ZHL-16C loading graph, nitrogen and helium, with the controlling compartment.
Multi-level profiles
Stack depth and time levels with per-level gas; tissue loading is carried continuously, including across repetitive dives.
CNS and OTU
Oxygen exposure tracked through the dive against the DTS reference PPO2 table and decayed across surface intervals.
Gas density limits
DAN and NEDU density caution and critical limits flagged at planned depth.
Min gas + lost gas
Rock-bottom reserve for a stressed ascent, plus a lost-gas contingency that re-plans the deco on your remaining cylinders.
ICD detection
Isobaric counterdiffusion warnings on gas switches, by N2 rise, partial pressure and the 4:1 ratio rule.
Team + instructor sign-off
Every diver verifies and approves the plan; the instructor gives final sign-off. Per-diver certifications with dive prerequisites.
Gas blending + cost
Partial-pressure blending with cylinder library and per-litre blend cost.
Altitude
ICAO standard-atmosphere correction; ceilings, NDL and schedules adjust automatically.
Post-dive debrief + no-fly
Compare plan against actual, with a no-fly / desaturation time estimate after the dive.
Shearwater import
Bluetooth dive-log import from a Shearwater (Perdix / Petrel / Teric / NERD 2): depth, ppO2, temperature, gas and deco, on the apps and the web.
Log, sites + mix library
Dive log with profile graphs and residual-exposure carryover, a shared dive-site library and a cloud-synced gas-mix library.
Metric or imperial
Work in metres and bar or feet and psi; the engine stays in SI and converts only at display.
The engine
Trustworthy numbers.
The decompression core is a pure, unit-tested Buhlmann implementation whose float runtime accumulation matches MultiDeco output exactly. The same maths that ran on the dive below.
Built by a technical diver
Will Goodman, Black Water Tek.
DTS is built by the diver who needs it to be right. Will is a TDI Advanced Trimix Instructor Trainer, JJ-CCR specialist and O'Three ambassador, with more than 10,000 logged dives.
- 290 m world record for the deepest dive on an unmodified CCR, 2014
- 6,000+ dives on closed-circuit rebreathers
- 3 x Guinness World Records for the longest saltwater scuba dive
- 20 years teaching technical diving around the world, currently based on the Gili Islands, Indonesia
Pricing
Two products. Pick where you dive.
DTS Gas Guru is a standalone app you buy once on the stores. DTS v3.0 is the full planner: everything Gas Guru does, plus complete decompression planning, a dive log and team tools.
Gas Guru
- MOD, EAD, END and gas density
- Best mix for depth and narcotic limit
- Nitrox and trimix blending
- Eight languages, fully offline
DTS Pro
- Everything in Gas Guru, plus
- Full OC and CCR decompression planning
- Stage cylinders + tissue graph
- Multi-level, altitude, repetitive dives
- Dive log, Shearwater import and cloud sync
DTS Instructor
- Everything in DTS Pro, plus
- Team management
- Team plan sign-off and briefing
- Student plan review
Questions
Frequently asked.
Straight answers on the engine, the products and how DTS fits into a technical dive.
What decompression model does DTS use?
DTS runs Buhlmann ZHL-16C with 16 tissue compartments and user-set gradient factors (GF Low and GF High), the same model family used by Shearwater dive computers. The engine is unit-tested and its float runtime accumulation matches MultiDeco output exactly.
What is the difference between DTS Gas Guru and DTS v3.0 Dive To Survive?
DTS Gas Guru is a standalone gas calculator: MOD, EAD, END, gas density, best mix and nitrox/trimix blending. DTS v3.0 Dive To Survive includes everything Gas Guru does and adds full open-circuit and closed-circuit decompression planning, stage cylinders, multi-level profiles, a dive log and team sign-off. Both share the same Buhlmann engine.
Does DTS support closed-circuit rebreather (CCR) diving?
Yes. DTS v3.0 plans closed-circuit dives with a full setpoint model for descent, per-level bottom and decompression, plus worst-case open-circuit bailout schedules. It also imports dives from Shearwater computers over Bluetooth.
Is there a free version?
No. DTS Gas Guru is a paid app on the App Store and Google Play. DTS v3.0 is offered as DTS Pro (49 USD per year) and DTS Instructor (99 USD per year).
Can I import dives from my Shearwater?
Yes. DTS v3.0 pulls dives straight off a Shearwater Perdix over Bluetooth, including depth, ppO2, temperature, decompression and gas, into the dive log.
Is DTS a replacement for my dive computer?
No. DTS is a planning aid. Always verify every schedule against your own dive computer and training. Technical diving carries a risk of serious injury or death.
Get the apps
Download DTS.
DTS Gas Guru is live on the App Store and Google Play. The DTS v3.0 planner runs on the web today, with native apps in build.