What is included in the regulator rebuild service?

All our hydrotests include removal and reinstallation of your regulator. Most people, and even most paintball shops don’t have the correct tools to do this to ASTM standards. We recommend you let us do it unless you have the tools and knowledge. We’ll take your regulator off, set it aside, test your bottle and reinstall it.

Our regulator rebuild service includes disassembly of the regulator, cleaning it out and replacing O-rings. We’ll replace the O-ring between the bottle and the tank, piston O-rings, and the fill nipple O-ring. These O-rings take the most abuse. They are on the inside of the regulator where you can’t see them, so most people forget about them until it’s too late. We’ll also replace the set screws on the regulator as needed. After we’re done, we’ll check for leaks around the gauge and burst disks. We’ll seal any leaks we find. We also check the regulator for output pressure and flow. If you have a desired output pressure for your regulator please let us know in the order notes.

Ninja regulator example

Our service doesn’t include replacing gauges, burst disks, bonnets, and bonnet O-rings. A replacement gauge is $14.95-$21.95 and we’re happy to replace it while we’re doing the service, but it needs to be paid for separately. Bonnets are anywhere from $19.99 to $39.99. The internal bonnet O-rings for some of the bonnets isn’t made anymore, luckily they seem to last forever. If we find an issue that’s not covered, we’ll reach out with a quote.

If you’d like any additional parts installed while we are rebuilding the regulator, just add them to your cart. If we see a new bonnet, or new gauge with your regulator rebuild we’ll do it while it’s on the bench. A failure in your regulator most likely will lead to a failure in your paintball marker. Replacing the O-rings every five years along with the hydrotest is a smart investment.

For a list of replacement regulators, and regulator parts check out our store at shop.hogansalleypaintball.com

Nick Morrione, Hydrotester

Why is grip tape illegal?

A lot of tanks come in with grip tape on the bottom. Federal law requires us to remove it, it’s a pain. Please don’t put it on your tank. Buy a silicone tank grip, they are cheap and easy to take on and off. By law tanks can’t be filled or hydrostatically tested with tape or stickers on them. This is because the DOT realizes that there is a person out there dumb enough to cover up tank damage with tape, or a sticker in order to hide damage and keep using their tank. It would be crazy dangerous. At each fill, the fill station operator is required to perform a visual inspection of the exterior of the bottle looking for physical damage. Tape and stickers prevent a full inspection and need to be removed. In addition to that for a hydro test if a piece of tape or sticker came loose after being soaked under water while in the machine it could damage our testing machine. We remove all tape, stickers, tank covers, etc before putting the tank in the hydro tester.

Check out our selection of reusable tank grips here:


Nick Morrione, Hydrotester

What is an ISO tank? Can you test them?

UN ISO tank
UN ISO bottle submitted for hydro test

We do test UN ISO tanks. We can’t test tanks that don’t have the UN circle logo before the ISO number. A UN ISO is the European standard for air tanks much like our DOT/ PHMSA standards to insure safety. In 2006 a trade agreement with the EU allowed the sale and use of UN ISO bottles in the United States. The European Committee for Standardization (CEN) tests, monitors, and qualifies the standards with the International Organization for Standards (ISO). Any UN qualified ISO bottle has undergone thorough independent testing and will be safe. If the just has an ISO number there is no guarantee that those standards match up to the bottles with DOT/PHMSA approvals and are not allowed for use in the U.S.

In summary, if your tank has the UN encircled symbol in front of the ISO number, you are good. You can buy, sell, fill, and get your tank hydro tested. If you don’t have the encircled UN symbol your tank was never supposed to be sold in the U.S., Canada, or European Union and it can’t be filled or hydro tested in the U.S.

This blog was written by Nick Morrione. References include: 49 CFR 180.207, ISO 11623-2002, Part 5 of the United States Code 552(a) and Part 1 of the Code of Regulations 51 from date of action 71 FR 33894, June 12, 2006.

Internal tank corrosion

pitting in cylinder

Tank corrosion can sneak up on you and ruin your tank.  We recently failed a fiber wrapped paintball tank due to internal corrosion that pitted the inside of the cylinder.  This tank was only 8 years old.

Pitting caused by corrosion hidden inside of the cylinder.

I may not look like much, but it was deep enough to cause a pin hole leak in the side of the tank.  That type of structural defect can lead to a much bigger safety issue.

What caused the pitting?  Most likely it was contaminates in the air as the tank was being filled.  If the air was properly filtered it most likely wouldn’t have occured.  It’s important that suppliers change their filters regularly to ensure the best quality air.  We’ve seen new economical pumps or compressors marketed to the home user to fill their own tanks at home.  Many of these systems have no real filter at all and many contaminants can find their way into tank causing damage over time.

SCUBA shops have been fighting corrosion since the beginning as salt is a major cause of pitting.  Paintball, airsoft, and PCP air rifle air suppliers are newer to this area and may have some catching up to do.  SCUBA shops require a visual inspection for internal corrosion yearly.  This catches the corrosion and halts it quickly before it has a chance to cause real damage.  Paintball, airsoft, and PCP air rifle customers typically only have their tanks inspected once every 5 years.  So that little corrosion that could have been rinsed out year one, couldn’t lead to a cylinder failure in year 8.

Consider the cost of more frequent inspections with replacing the entire cylinder and hopefully the cylinder will fail inspection before it has a chance to fail catastrophically in the field.

Nick Morrione

What is a visual eddy test?

There is some confusion between a SCUBA visual exam, a visual inspection,  and a visual eddy current test.  All tank filling personnel are required to conduct a visual inspection of the outside of the tank to make sure there is no visible damage that could compromise the integrity of the tank.  We’re looking for dents, dings, and gouges.  The cost of the visual inspection is including in the cost to fill.

A SCUBA visual exam is done on breathing air tanks periodically.  The tank is emptied, and the valve is removed so they can look inside the tank for any corrosion, mold, or debris that could have accumulated in the tank and get into your regulator or lungs.  Most SCUBA shops charge $10-$15 for a visual.  If you use your SCUBA tank for an airgun or paintball marker and never for breathing, you don’t need a periodic SCUBA visual exam.  We do a complete Visual exam at the time of hydro testing.

A visual eddy current test checks tanks for sustained load cracking around the valve.  We use a probe that has an electrical current and creates a magnetic field which can highlight cracks in the aluminum.  Cracks are bad for everyone.  Aluminum tanks need to have some elasticity so they can expand as they are filled.  A crack is a clear indication that the aluminum won’t expand at that point, and the crack will widen.  Aluminum tanks made prior to July 1990 could have been made with 6351 aluminum alloy.  Some manufacturers started switching over to 6061 aluminum alloy as early as 1988.  Most fill personnel require anything made prior to 7/90 to have a visual eddy inspection at the time of the hydro test.

It’s important here to note that a if a tank doesn’t pass a visual inspection or a visual eddy current test it can’t be filled.  But tanks that don’t pass a SCUBA visual inspection can usually just be cleaned out and filled up.  I personally think beverage tanks should get a yearly SCUBA style internal inspection.  With home kegerator systems becoming increasing popular there runs a risk of bacteria growing in the tank and tainting the beverages.  For example, if there is a leak in the airline causing the tank to empty while the keg is still pressurized, beverages can back fill into the tank and start growing bacteria at a rapid pace.  if you have a beverage cylinder and have seen fluid in the lines between the keg and the tank ask for an internal visual inspection.  If your lines aren’t transparent, think about changing out a section to one that is.

I hope this answers some questions and keeps some people safe.  Please feel free to contact us with any questions.


How do I know if my tank is out of date?

Every tank is labeled with the date of manufacture and your hydro testing schedule is based off of that.  Looking over your label you’ll see lots of information, but you really only need two or three things.  The date of manufacture, the last hydro test if applicable, and the PHMSA exemption number.

Paintball tank label
Example of a label

In the picture above the first line is the regulatory information for Canada’s testing standards.  The second line is the US exemption or now called the special permit number.  The “DOT” has been replaced with “SP” on more recent bottles.  The third line is the serial number.  The fourth line is the date of manufacture.  If there was a more recent hydro, it should be adjacent to the date of manufacture for ease of locating.

The date of manufacture is the month followed by a symbol or number and then the two digit year.  The date in the bottle above is May 2003.  Which puts the end of life date at the end of May 2018.  So as of this article being written this tank is best used as a windchime and can’t be tested or filled.  All fiber wrapped tanks have a fifteen year lifespan, but the solid aluminum paintball tanks can be tested until they fail.

To know how long your tank has between hydro tests, go to:  https://www.phmsa.dot.gov/approvals-and-permits/hazmat/special-permits-search  and enter in the E or SP number.  For example E 10945 as in the picture above.  There will be a paragraph labeled testing, and it will indicate how long the period between tests is.

If you have any questions, take a picture of your tank and email it to us at info@paintballhydro.com

Thanks for reading!  Nick.

How to judge the quality of a hydro-test facility

Daniel Hogan, one of founding partners has always stated that the end consumer doesn’t know the results of the quality of the hydro-test, they only see the stamp on the bottle.  That being said, it stands to reason that a company that doesn’t spend much time or effort to properly label your tank after testing may not have put much effort into testing it.  Here at paintball hydro we understand that paintball tanks are exposed to PEG (the fill of a paintball), sunlight, moisture, and generally being tossed into gear bags or rubbed on the ground.  To combat these issues, we make sure to overcoat our hydro labels with a solid coat of high grade epoxy to make sure they stay on.

We test the integrity of the threads on each bottle with a no-go gauge to ensure the threads are deep enough for the valve not to blow off.  Ninja paintball is the only other company that we know of that does this, probably because they know something about the bottles they sell.  Paintball players who fly frequently with their bottles take the valves on and off for the TSA should be especially concerned with this issue.  Most players only have their valve off every five years for testing, and it’s less of a concern.  Pro players who have had the valve removed and reinstalled several times usually sell off their old bottles and there are lots of used bottles out there.

Fiber wrapped bottles take time and patience to test properly.  We love this sport and we wouldn’t speed our way through a test because the fiber wrapped bottles take longer to test than a solid aluminum or steel tank.  We understand the consequences of a bottle failing out in the real world while someone is holding it.

Hydro tests cost about the same everywhere, so it makes sense to go with a company that you trust and who understands what paintball cylinders go through in their lifespan.  Check out their website, talk to someone who works there, and go with a company you trust.