Clean gas.
Honest fills.

Full-service technical diving gas station serving the St. Louis dive community, and every diver is welcome. From a recreational single-tank air fill before the quarry to custom trimix blends for the deep stuff, we mix it right, check it twice, and never rush a fill.

3442

PSI Fill Pressure

99.5%

O₂ Grade Purity

Days a week by Appointment

/ 01

Compressed Air Fills

Filtered, dry, breathing-grade Grade-E air fills to 3442 PSI. Bauer compressor with high purity filtration. By appointment, and air fills are done while you wait at drop-off.

That same clean air fills paintball and HPA (high-pressure air) tanks up to 3600 PSI, too. Just bring the fill adapter for your tank and we'll top it off.

Grade E Breathing Air Up to 3442 PSI Paintball / HPA tanks All divers welcome

Starting at

$10

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Nitrox Blending

Partial-pressure blending for EAN 32, 36, or any custom mix from 22% up to 100%. EAN 22-40% is $20, 41-100% is $40, any size SCUBA tank. Every blend is analyzed by you and us before it leaves the shop. Bring your analyzer or borrow ours.

EAN 22-40% Enriched to 100% Any size tank Verified twice

Any size tank

$20 / $40

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Trimix & Heliox Blending

Custom helium-based blends for cave, wreck, and deep diving, mixed with UHP (ultra-high-purity) helium on every blend. Bring your gas requirements and I'll fill your tank.

UHP helium Custom He mixes Deco gases CCR diluent Bailout stages

$40 + $3/cu ft for He/ tank

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100% O₂ Fills

We fill aviator-grade (ABO) oxygen for decompression cylinders, CCR oxygen tanks, and rebreather bailouts. All O₂ service equipment is dedicated and oxygen-cleaned. Price covers AL40 or smaller; larger tanks are more.

Aviator grade is held to a tight moisture limit, so it stays dry. Medical O₂ can carry enough water vapor to freeze a regulator at depth or invite internal corrosion, so the drier gas means cleaner tanks and regulators you can trust.

Aviator grade (ABO) 99.5% min purity Low moisture / dry O₂-clean tanks only

Per fill AL40 or smaller

$20

/ 05

Visual Inspections (VIP)

Annual visual inspection per PSI/PCI standards. I pull the valve, inspect the tank interior, check the neck threads, re-grease or replace the o-ring, and issue a fresh VIP sticker. Air fill is included.

A cylinder holds thousands of PSI, and the trouble hides inside. Moisture, rust, and cracks form where you can't see them, so a tank that looks fine can be unsafe within. It's why most fill stations require a current sticker before filling.

No hydrostatic testing. A visual inspection is not a hydro test. I do not perform hydrostatic (hydro) testing and I do not send cylinders out for it. Your tank needs a current hydro stamp within the last five years before I can fill it. If yours is out of date, take it to a DOT-licensed hydro facility first.

PSI-certified Required to fill No hydro testing

VIP+Air Fill from

$20

Every tank is CO-analyzed
before it leaves the shop.

Carbon monoxide is the one contaminant you can't catch on your own. It's colorless, odorless, and tasteless, so a bad fill smells and tastes exactly like a good one. The trouble is that CO binds to your blood far more readily than oxygen, and the deeper you go the worse it gets, the same trace amount becomes meaningfully more potent under pressure at depth.

Contaminated fills are rare, and that's exactly the point: they happen rarely enough that nobody expects one, which is why a quick analysis matters. We test for it so you never have to wonder. It's a small step that takes the guesswork out of the most important gas you breathe.

Who's behind the fill

I'm Chad. First and foremost a cave diver, happiest deep in a spring where it's just me, a good dive buddy, the guideline, and the dark. But I'll take any excuse to get wet: reef, wreck, or a cold Missouri quarry, it's all good underwater. During the week I'm a software developer. Nights and weekends, I'm at the bench.

The fill station started as a way to keep my own tanks full. It turned into a hobby of its own, and now I run it for the local dive community, clean air, honest technical mixes, and someone behind the panel who actually dives what he blends.

The bench behind every fill.

Bauer Capitano compressor with auto condensate dump and high capacity Grade E breathing filters. Connected to 2 High Pressure Banks and an Ingersoll Rand blending panel. Oxygen and Helium on tap for blending. Electronic and air powered booster.

Bauer compressor High-purity filtration Partial-pressure blending CO-analyzed

Clean gas.
Honest fills.