Tank filtration/plant filtration help

Hi, I'm in the process of setting up a new tank. I have never owned an axolotl or any other Caudata so I'm new to this. I've been reading and asking around for advice on what the best tank set up is and I was hoping to check if my plans would work and be safe for the axolotl.
I will be getting a 10 gallon tank (I'm hoping for a bit more length than the standard 20x10x10 inches). I'm probably not going to use substrate, if I do it will be sand.The main thing I'm wondering about are filters and plants.
My teacher keeps an axolotl and he has this plant/filter duo that he set up. The plant was kept in a milk/water jug (the plastic ones with handles) and he had running water coming out of this. He said that this was his filter. I'm guessing there was a filter in/coming through the potted plant. I'll try to post a picture of it later/ask him more details (he was in a rush when spoke to him).
I was thinking this might be a good idea but I was having trouble with figuring out how I would set it up and if it was even alright for the axolotl. Here are some of my questions/concerns:
I'm assuming an in-the-tank filter was used but would the water flow from it be too strong for the axolotl? Is using a plastic jug even safe? What could I do to make it aquarium safe? What type of plants would be okay to use in this situation? The plant would have to be rooted I'm guessing so what should be used to root it? Since it's in a jug/contained, is using gravel safe or is it a risk not to be taken? What kind of filter (in your opinion) would be best to use in this set up and how should it be placed? Can this idea even be considered?
If this idea is a no go, I'm will probably use a sponge filter (that would be appropriate for my tank size). I still would like to have some plants in the tank nonetheless (I'm hoping to use marimo "moss" balls, Spathiphyllum, and maybe Ceratophyllum).
I understand that it might be hard to get a sense of what I'm trying to describe but if anyone has any input on any of this or might even have a set up kind of like this, I'd love to hear about it! Thanks for reading.

He probably just had the roots sitting in a HOB filter. It's perfectly fine. I keep golden pathos in my tank on the top which I think helps maintain water quality. You can use other plants such as water lillies too.

To answer your question - it will be fine. I personally would not use the plastic but I see it fairly harmless.

I don't think a PLANT sitting in an HOB would provide much filtration....? This seems to be a popular trend lately, a faux 'aquaponics' system and it's just kinda useless in my opinion.

I'd go with a sponge filter - much safer and healthier for the axie.

A HOB (hang on back) filter planted with terrestrial, aquaponic plants would provide excellent biological filtration to the aquarium. Because the terrestrial plants are able to exchange gases more efficiently than aquatic ones, they grow significantly faster, and while doing so absorb significant amounts of nutrients from the water column. I suppose there's also a benefit from doing this in that it would decrease the flow coming from the filter.

I think filling a mesh bag with gravel, or hydroton (expanded clay pellets) would be a good way to plant them in the filter. This would make cleaning easier and help prevent the plant's roots from clogging the inside of the filter. Do a search on the Plantedtank forum on planted HOBs and you'll find some good examples.

Good plants for this would be the peace lily, arrowhead plant, pothos vine (although doesn't stay very organized), lucky bamboo, and the aluminum plant (with many other pilea species). Java moss would also work in the filter's outlet, growing semi-aquatically and decreasing flow.

Anything that increases surface area for bacteria will add some additional filtration, and any plant will use up some nitrates.
Since most filters and airline tubing are plastic, a plastic jug shouldn't be any less safe - if you are concerned about chemicals from the plastic leaching into the water, you could fill the jug up with water, let it sit a few days, and then replace the water and do this a couple times. That will get rid of the most 'leachable' chemicals. The amphibian research lab where I worked for a couple years did this with new tubs - I have no idea if they needed to do this, but it made everyone feel better and the frogs did pretty well, so there you go.

Just make sure any plant you use isn't toxic, and it should be fine. You've actually given me the idea to move some of my cutting over to the filter in my tank. Hmmm....

By the way, I have Java fern in my axolotl tank, and it does great. Doesn't mind the lower light levels, doesn't mind being dug up by axolotls....looks good...

Huh, that is interesting...

I set up some pothos vine cuttings in the filter last night. So far so good, in that it doesn't seem to affect the axolotls or the guppies in any way.

Thinking of ways to modify a HOB filter to incorporate more plant filtration - will update if I come up with anything interesting

I've seen some set ups that use a partial cover that allows potted terrestrial plants to extend their roots directly into the water column. A 10 gallon might have its limitations though.

Here are some photos of the setup I was trying to describe. Also thanks for all the input, it's greatly appreciated. I think I'm going to try it and see how it works out. Glad it's going alright for you kjnorman! Also, I'm still not sure what type of filter is being used in the pictures... Anyone have any idea? I'm guessing it's a set-in one but I'm not too familiar with filter types. Also there doesn't seem to be anything dispersing the flow... Is that something that would be needed in this case?