BART-HAB: Total bacteria tests

[plankton123]

Craig/Randy,

BART-HAB, or total heterotrophic aeorobic bacteria tests, are a bit on the pricey side ($15 per from ESV, $7 from the source in Canada if you can get it) so I was wondering if one could be made by hobbiest for the hobbiest so they could be run periodically to test total aerobic bactera?

The basic design looks like a simple Glycerol/Peptone auger growth medium with Methylene blue used as the indicator and alternate oxygen souce. The amount of time it takes to deplete a fixed amount of indicator can correlate with bacteria density and bacteria 'strength'. It has even been said that the pattern of indicator usage can indicate the type/species of bacteria.

To me, it looks like the biggest problem would be making sure that the test tube/growth media is sterile and free of airborne bacteria, etc.

What I'd like to see is a plot of total bacteria over time and see if any events in bacteria growth can be correlated with ORP and physical changes in corals (RTN, growth spurts, polyp extention), etc.

Whatcha think?

http://www.dbi.sk.ca/droycon/HAB.html

Scott

 

[CraigBingman]

You are correct, the units are a bit pricey, especially if you want to use them frequently.

I suspect that Standard Methods has instructions for how to construct BART tests. From the standpoint of hobbyist assembly, the problem is that the units will need to be sterilized. That means that all of the components that you use will need to be OK in 20 psi of steam for 20 minutes. Then of course you need to supply that environment, which means running a pressure cooker in your kitchen. The disposable plastic components in the commercial units may or may not be up to steam sterilization. They may use radiation sterlization in their commercial process. Obviously that isn't an option at home.

If you had accumulated 10 or so used BART units, and you happen to have a pressure cooker at home, then you might want to see if you can get away with reusing the plasticware. Ideally, you would autoclave the used BART units before opening them and cleaning them out. This is because you have basically no idea what might be growing in them, and for all you know, you might have a concentrated soup of pathogenic bacteria there. WARNING: bacteria stink when they grow, and they smell even worse for a little while when you heat them up, so expect some [strongly] objectionable odors when you steam sterilize the used units.

A less desirable route would be to wear gloves and bleach the used BART units, then neutralize them. This method is less desirable because when you open the units, you can easily generate aerosols of pathogenic bacteria.

A more satisfactory option might be to find new materials that can be used for fabricating home-BARTs. They look more or less like 50 mL disposable centrifuge tubes, loaded with liquid bacterial growth medium (spiked with methyelene blue) with a ping-pong ball floating on top of the liquid to slow down surface uptake of oxygen. I don't know off the top of my head if a ping-pong ball is the right diameter to fit a 50 mL centrifuge tube, or if it will take 20 psi steam for 20 minutes or not. If it does, I'd say it would be relatively easy to whack together something like this at home.

I guess my underview is that the units aren't horribly overpriced if you count your time as being worth something. True, they aren't inexpensive, but they aren't tremendously overpriced, either. No matter how you slice it, it will take at least an hour of clock time for you to put together a batch of these units, even if you have my level of skill. You would be able to process a few dozen of them at a time. You would need to either recycle them (which is either stinky or dangerous) or chase down sources of new materials for the units and put them together from scratch each time.

If there is widespread interest, I guess that I could put in some library time and do some materials tests. But that is about all I can do to help you off the top of my head.

Craig

 

[plankton123]

Craig,

Great to hear from you and thanks for the
reply.

I actually do have a lot of centrifuge tubes
and have found some plastic balls that fit just
right. I was thinking of a simple auger/sugar
growth medium (spiked with methylene blue) and
'incubating' them just at house temperature. I
sort of assumed that I there wouldn't be any
pathogenic bacteria growing in my tank that
would be dangerous to humans. But, you've
made me think twice about that. I was also
planning on only using the tubs once since the
only practical means I have to sterialize them
is via bleach. What I might do first is order
a set of 9 from the canadian supplier then run
those plus mine in parallel and see if the results
are comparable. The cost of the 9 from canada
would be about $90. Mine would cost between free
and $500 depending on what hourly wage I want
to assign to my time spent making them. VBG

Again, thanks for info and will email when I
can actually complete my little study. To tell
you the truth I'm very curious about what bacterial levels my tank is at now and what happens each time I mix a portion of my sand bed
and how long it takes the tank to stabilze afterwards.

Later...

Scott

 

[CraigBingman]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by plankton123:
<strong>Craig,


I actually do have a lot of centrifuge tubes
and have found some plastic balls that fit just
right. I was thinking of a simple auger/sugar
growth medium (spiked with methylene blue) and
'incubating' them just at house temperature. I
sort of assumed that I there wouldn't be any
pathogenic bacteria growing in my tank that
would be dangerous to humans. But, you've
made me think twice about that. I was also
planning on only using the tubs once since the
only practical means I have to sterialize them
is via bleach. What I might do first is order
a set of 9 from the canadian supplier then run
those plus mine in parallel and see if the results
are comparable.

</strong><hr></blockquote>

Just a couple of comments.

First, although I've never seen one of these BART thingies in person, I doubt that there is any agar in the bacterial growth medium. I'd guess that for heterotrophic bacteria, they are using some sort of rich growth medium (containing peptone and yeast extract) in addition to possibly a sugar carbon source.

You might want to look around to see if you can find a source for liquid LB, which is a commonly used rich growth medium.

It is most definitely possible to culture human pathogens from seawater. Be careful with this stuff.

Whatever you do, you will definitely need to do a calibration with the commercial units.

I might have a chance to look in Standard Methods for more information on this test method. That won't happen for a couple of weeks, though. I have a club talk in LA and a vacation coming up this week, and a very demanding daytime gig.

Craig Bingman

 

[jamesw]

Hi folks,

These units are regularly used in my industry (Pipelines) to check for the presence of sulfate reducing bacteria or acid producing bacteria which can cause pitting to the inner wall of the pipeline.

I've seen them advertised in Pipeline and Gas magazine. I'll try to track down a copy when I get to work tomorrow. Perhaps this is a cheaper source than an "aquarium supplier."

[Edit - I just reread your post and noticed if you are interested in the heterotrophic aerobic tests, so I can check on those too, not just the anaerobic.]

HTH
James Wiseman

[ April 08, 2002: Message edited by: jamesw ]</p>

 

[plankton123]

Craig,

Thanks for the warning. Just bought a box of 9 HAB-BART test kits from DROYCON BIOCONCEPTS INC in Canada for $77.25 ($65.25 plus $12 S&H) and should get them in a week. They're really nice folks to work with.

Yes, I was wrong about the Agar. If you look up the HAB test kits on the Material Safety Data Sheet (MSDS) it clearly says the test kits contain:

Glycerol
Peptone
Tryptone
Sodium Thiosulphate
Magnesium Sulphate
Dipotassium Phosphate

The latter I guess are just preservatives.

For fun, I'll probably give a couple to some folks in our local reef club (same colleagues who helped host the Western Marine Conference in Monterey last April) to see what the total aerobic bacteria levels are in their tanks. Some of the reef tanks have been up for many years (>10).

PS If you happen to stumble on the standard protocol for aerobic bacteria and want to pass it along that would be great, but don't go to any great lengths to get it.

Ahh, I love playing with new tools...

Scott

 

[plankton123]

James,

The BART tests are used in many, many areas for testing for the presence of many kinds of bacteria. Hach has them (although it takes quite awhile to get through their website and you have to register before you can evern get a quote) but they cost more. WRT aquarium suppliers, ESV has them but basically charges twice then what you can get the source or from Hach. But, ESV I think was the first aquarium supplier to stock them so I guess they can name their own price.

I agree with Harker on this one that this might be another important means of judging how effective our filtration systems are since if a tank as unusually high levels of active bacteria then the filtration systems clearly can't handle the input and some action to reduce the bacteria levels needs to take place. e.g. less feedings, stocking levels, more/better filtration, water changes, etc. It will also be interesting to see how much higher the bacteria populations are in our reef tanks compared to levels recorded in different seas and reef environments.

Later...

Scott

 

[CraigBingman]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by plankton123:
<strong>Craig,

Thanks for the warning. Just bought a box of 9 HAB-BART test kits from DROYCON BIOCONCEPTS INC in Canada for $77.25 ($65.25 plus $12 S&H) and should get them in a week. They're really nice folks to work with.

Yes, I was wrong about the Agar. If you look up the HAB test kits on the Material Safety Data Sheet (MSDS) it clearly says the test kits contain:

Glycerol
Peptone
Tryptone
Sodium Thiosulphate
Magnesium Sulphate
Dipotassium Phosphate

The latter I guess are just preservatives.

Scott</strong><hr></blockquote>

No, the magnesium, potassium, phosphate and sulfate are there to support bacterial growth. Mg, K, P and S are all essential to life. The main carbon source is glycerol in this test, and the peptone and tryptone are rich, complex nitrogen sources with other tasty goodies as well. ;-)

Craig