I have not used Anaero Technology, but it looks impressive.

Now, if you are looking for a good reliable technology definitely go for AMPTS II. Here are some publications about the advantages and disadvantages of AMPTS II.

Update: We are currently in the process of purchasing the Anaero Technology Nautilus BMP system. The entire unit seems promising and it has ports for sampling the liquid phase. There is also flexibility in where the gas scrubber unit can be placed. Will update once we actually have the unit.

@ Lea Chua Tan

so – did you end up buying this system?

I would be very interested in your experience with the Nautilus setup since I am in the process of purchasing a new BMP system.

Maybe you could share some insight on ease of use, reliability etc.

I am a bit concerned about the use of HDPE bottles in regards of gas permeability – is there any noticeable effect in gas amount or concentration?

your help is highly appreciated!

Hi Vincent Plogsties

Yup, we ended up buying the system. It has its ups and downs and generally, it has been working fine.

Regarding you question about gas permeability, the bottles are all submerge inside the water bath and encase within the water bath so I am unable to check if gas is leaking out. However, since it is connected to the gas meter, it might not be an issue, the gas will immediately flow up to the gas meter. I find it more troublesome to clean the HDPE bottles since it stains easily but it can be autoclave so I am not worried about contamination.

In summary:

Pros

1. Cheaper

2. Able to take liquid samples without opening the bottles

3. The gas meter arduino system can be connected before or after the gas scrubber and also can be connected to other reactors not related to the system itself

Cons

1. System is not as user friendly with the program and data gathering - computer have to connected and all data have to be downloaded every time (it is not online)

2. The entire system is difficult to clean

3. Manual calibration of the gas flow meter (can be a pro and con depending on how you look at it)

Let me know if this helps. The one thing that the supplier of Nautilus informed me that they are continuously working on upgrades so maybe the cons I listed out will soon be take care of. They did mentioned that they are developing a way to have glass reactors instead of HDPE bottles.

Hi Lea Chua Tan

thanks for the quick reply - I really appreciate it!

to clarify: my question about gas permeation was not about visual gas leaking. My concerns were about different permeation rates of CO2 and CH4 through the bottle walls leading to incorrect gas concentrations.

I think one would notice it by unusual high amounts of methane. Maybe this is hard to detect with this system because there usually is only one gas analysis in the end.

Also - since you are using gas scrubbers - this problem doesn't really apply to you, I believe.

Anyway - complicated data gathering and test set-ups are big negatives for me at least with bigger tests.

They at least advertised remote access and touchscreen controllers in the leaflet you posted - which would be a big step towards ease of use. But this seems not to be part of your system and also is not mentioned in the user manual I downloaded from their homepage.

Again thanks for your help!

Good afternoon and apologies but I had not seen this conversation.

Regarding Lea's cons we think they do not detract from the data quality and overall ease of use of the machines and, yes we are always working on upgrades that do not leave behind our previous customers. That is our commitment:

1. Program not user friendly. We have had an issue with the commas in the csv data files which temporarily we address adding a suitable laptop to ensure this is no difficulty to using the machines seamlessly. We did learn from our experience in Ireland. Also, we learn to make the modifications in Excel on comma and colon delimiters. As well as that, we are developing a totally new software that will take care of that, and will be free download.

2. Ease of cleaning. This really is a matter of getting used to and having some simple cheap tools, such as a toilet brush and ....that's it. I have just prepared 4 complete sets (60 reactors) and it does take time, because of the quantity, but the wide mouths make it very easy to clean well inside. You are correct, the bottles can be autoclaved, and also apart from not breaking easily are standard bottles you can buy directly from scientific suppliers such as VWR. This was our intention from design: to ensure durability, avoid damage and have something that can be replaced easily in the worst case. Regarding the staining, this is one thing we can not eliminate. We have thought about using gas bottles, and might use them at some point in the future; but hand in heart, the benefit in the context of a BMP test of seeing through in a dark liquid submerged in a water bath is limited. I get shaky hands every now and then and knowing I can't break those bottles even if I dropped them, especially when preparing lots, reassures me. Our biggest client now have 26 Nautilus machines in one single lab and they work them non stop. To address Lea's comment we are actually developing at this very moment something we call: AD Survival Pack. It contains those little things that make using any BMP machine extremely easy and efficient. You are right Lea, sometimes even not having a right size beaker, or a suitable spatula can mess slow us down. The pack will include, precisely even some buckets we have found ideal for the clean up process, and we are also making hose disconnections much easier.

3- Manual calibration of gas flow meter. On this one I will be a little defensive, but it is for a good, honest reason. We tested several designs of gas flow meter by our own means and found, reasonably, that even if a cell has a "calibrated value" this is not consistent and it really is not possible to guarantee all cells in a 15 cell gas flow meter will be exactly the same volume. Because we believe that the integrity of data is paramount in research we provide the ability to manually calibrate the cells and for the user to see directly what their machines is actually measuring. We are developing new methods of fabrication that should reduce the need to do calibrations and keep them closer. But, please do not feel bad, calibrating is painful but so important for us all to trust data.

On this point, please keep this in mind, today 16 July 2020, I tell all our existing clients, you will hear good news from us next year for you. I can not disclose this at the moment, but we are not in the business of gimmicks, it will be to the benefit of all. Be sure we work with all of you, because we need funds to survive, but money is not what drives us really, we love research :)

Vincent, as soon as conditions allow and it is convenient to you, we will visit you.

Thank you for your comments, they are not ignored and in fact, even though I just saw them now, I can tell you we have been working on all these fronts. However, the machines do the job, and do it consistently for many years.

Take care