I found some microbes that apparently are some type of bacteria and now i cant find protozoans

What are those things?

Someone know the specie?

Why the Protozoans are dying?

those things appeared in the water example and later all the protozoans died

I do not see anything recognizable in that image. What magnification is it? Where do you get your samples and is it possible that the water quality is degrading?

I have to say that at some point i have seen an image similar to that under the microscope in relation to paramecium but my interest in protozoa is limited to growing them as food for other animals and not technically accurate in any way...

I do not see anything recognizable in that image. What magnification is it? Where do you get your samples and is it possible that the water quality is degrading?

normal river water with lots of natural food (lettuce) and the magnification is 400X in the photo, and i can see in the 800X magnification this things are circles (bacteria)

So you have a bowl or something similar with lettuce in it? If the water just sits there for a longer time, the water quality will change. It is unlikely that bacteria are directly killing your eukaryotes, they are present all the time. However, they actively degrade the organic material in your water sample, resulting in unfavorable growth conditions, if the water is not replenished.

normal river water with lots of natural food (lettuce) and the magnification is 400X in the photo, and i can see in the 800X magnification this things are circles (bacteria)

How did you know you were dealing with "protozoa" in the first place?

How did you know you were dealing with "protozoa" in the first place?

i saw lots of paramecium in the slides and they disappeared and the bacterias replaced they (a lot of bacterias that looks like the ones in the photo)

i saw lots of paramecium in the slides and they disappeared and the bacterias replaced they (a lot of bacterias that looks like the ones in the photo)

I know nothing about paramecium but this YT was very odd.

So you have a bowl or something similar with lettuce in it? If the water just sits there for a longer time, the water quality will change. It is unlikely that bacteria are directly killing your eukaryotes, they are present all the time. However, they actively degrade the organic material in your water sample, resulting in unfavorable growth conditions, if the water is not replenished.

no i used a big bottle and it not stayed for long time just one month (for the last tests to replenish i waited 2 months or more with less water) but possibly the unfavorable conditions killed the eukaryotes but the lettuce is not totally degraded

The water would change much faster than for the lettuce to literally degrade. Biological activity are ongoing and one month or so is plenty to change water quality (just ask someone with an aquarium how it is going to be without filtration). Obviously this is speculation, as it is not clear how exhaustive your search was.

Edited October 22, 201411 yr by CharonY

I set up a 75 gallon aquarium two weeks ago with extensive filtration and lighting and I can already see a shift in life forms, a bottle with no aeration for a month...

in the first week i only saw Paramecium aurelia and didinium

in the second week i saw a lot of species of parameciums and didinium

in the third week they started to disappear and now i can only see bacterias, i know now the water dont have growing conditions but anyone known the specie of this bacteria???

Now I saw the water a lot of times again and the water is not totally deteriorated???

I can see parameciums in the bottom of the bottle but I cant see in the top of the bottle(where the bacteria is located).

Edited October 23, 201411 yr by Paramecium8

In that case you have just not been searching enough. Also note that Paramecium feeds on bacteria.