Seriously, ditch the BJT and find an N channel logic level MOSFET with a maximum drain current of at least 1A.
Tadelis:
DC 3-6V 120L/H Mini Submersible Water Pump – Art of Circuitsfound this link, I bought it in different store, but its the same as I use. I can't find a normal datasheet, but I thought this pump is really low current and won't be a problem controling it...
It is low current, a BJT ought to work, but why not measure the current to make sure? My suspicion is they've written the no-load current into the specs, which isn't useful.
MarkT:
It is low current, a BJT ought to work, but why not measure the current to make sure? My suspicion is they've written the no-load current into the specs, which isn't useful.
You mean power up the pump and then measure how much goes through?
PerryBebbington:
Seriously, ditch the BJT and find an N channel logic level MOSFET with a maximum drain current of at least 1A.
Can't find any good tutorial how to use them, everyone connects them differently and don't have a clue which way to go.
Tadelis:
Also I tried to test the circuit, switched the supply on and tested the pins that comes from transistor to pump, it gives 1.5V, in my undestanding when transistor is not saturated in those pins should be no voltage, but tried to pull HIGH the base pin and it gives 5V as it suppose to.
Voltage between collector and emitter should be 0 when no current comes to base, but in my circuit it's 1.5V so is it that transistor is damaged or is it normal?
Tadelis:
Can't find any good tutorial how to use [an N channel logic level MOSFET], everyone connects them differently and don't have a clue which way to go.
Can't find any good tutorial how to use them, everyone connects them differently and don't have a clue which way to go.
Ahem... reply #10, and reply #23.
Voltage between collector and emitter should be 0 when no current comes to base, but in my circuit it's 1.5V so is it that transistor is damaged or is it normal?
If the voltage between collector and emitter were 0V with the pump connected the pump would have 5V and would be running. The CE voltage when there is no current into the base should be the supply voltage, 5V.
If the voltage between collector and emitter were 0V with the pump connected the pump would have 5V and would be running. The CE voltage when there is no current into the base should be the supply voltage, 5V.
Okay maybe i explained it badly. I unpluged my water pump and between those pins 5V and ground that should connect to my water pump there is 5V voltage when current goes to base, and 1,5V when theres no current to base. In my undestranding it should be 0, not 1,5V, or am I wrong?
Ah! I didn't know you meant that. When you say 'no current to the base' what do you mean? Do you mean the base is disconnected? What is the voltage on the base? If you mean that there is nothing connected to the base or the collector then the voltage should be 0V. You say you unplugged the pump, is the diode still there? If it is and there is voltage on the collector that suggests the diode is leaky, which means it's probably faulty.
PerryBebbington:
Ah! I didn't know you meant that. When you say 'no current to the base' what do you mean? Do you mean the base is disconnected? What is the voltage on the base? If you mean that there is nothing connected to the base or the collector then the voltage should be 0V. You say you unplugged the pump, is the diode still there? If it is and there is voltage on the collector that suggests the diode is leaky, which means it's probably faulty.
Yes, there is a diode, and yes, there is nothing connected to base, i just tested it, so thats what I wanted to know if its a normal behavior, thank you very much. Now I think I'am going to use N channel MOSFET instead, I understand it opens when u pull gate HIGH, so esp32 only outputs 3.5V as I know, so MOSFET with gate threshold voltage should be around 2-3V? Any MOSFET suggestions maybe? Or am I wrong somewhere?
I understand it opens when you pull gate HIGH
Be careful in your choice of words. For a mechanical switch 'open' means not conducting or switched off, which I think is the opposite of what you mean. For a tap (water) 'open' means on, as in water flowing, in other words the terminology for water and electricity is back to front, one compared to the other.
An N channel MOSFET conducts when the gate voltage is positive with respect to the source, which is what you need.
MOSFET with gate threshold voltage should be around 2-3V?
'Gate threshold' means the point at which is just starts to conduct, not the point where it is well and truly on. You need one specifically designed as 'logic level', many such MOSFETs have an L in their part number. Unfortunately I don't have a recommendation as I have yet to need a MOSFET to control something of about 1A from 3V3. I was hoping someone else would say something. You are going to have to read some data sheets, look for the on resistance with Vgs at 3V3, you are looking for it to be as low as possible.
Be careful in your choice of words. For a mechanical switch 'open' means not conducting or switched off, which I think is the opposite of what you mean. For a tap (water) 'open' means on, as in water flowing, in other words the terminology for water and electricity is back to front, one compared to the other.
An N channel MOSFET conducts when the gate voltage is positive with respect to the source, which is what you need.
Thank you for correcting me, my native language is not English so sometimes its hard for me to express myself, especially with this electrical terminology.
I found one tutorial that uses this mosfet to control 12V dc motor
should I try this?
I know its a lot of questions, I don't want you to waste your time on me, so if u're not too busy then maybe help me :D, thanks for the answers, so far you helped me a lot to understand this.
MarkT:
It is low current, a BJT ought to work, but why not measure the current to make sure? My suspicion is they've written the no-load current into the specs, which isn't useful.
tested the pump current, from a battery it took 400mA and then slowly decreased to 200 mĄ, from a stable 5V power source it was always about 200mA. I measured without using it in water, so I'am guessing 400 mA is max that it draws when is used.
Thank you for correcting me, my native language is not English so sometimes its hard for me to express myself, especially with this electrical terminology.
Your English is fine. I didn't think the problem was that English was not your native language, I thought the problem was you being new to electronics and not knowing the quirks of electronic-speak.
The MOSFET is not suitable, it is not logic level. The gate threshold is 2V to 4V, so it might not turn on even a little bit at 3V3. Also, it is rated for 49A, which is a bit of overkill!
I don't want you to waste your time on me, so if you're not too busy then maybe help me
I am not too busy (corona virus 
) but I also don't want to just give you answers, I want you to find out for yourself. I could probably find you a MOSFET, but I want you to put the effort in, you will learn by doing so.
I am not too busy (corona virus
I understand that it helps to learn, and I know I really need to learn :D, I'll try my best to find it. Its just that I need a lot to do with my project for my university and deadline is very near, I thought it will work and I'll be okay, but then esp32 fried and made a mess of my project, there a lot of work I also need to do, and this really puts me in tight spot, stress really doesn't help with learning 
RS Components have the best search facility of any web site I have ever come across. The link is to their selection of MOSFETS, hopefully that will help you find one.
Tadelis:
Can't find any good tutorial how to use them, everyone connects them differently and don't have a clue which way to go.
MOSFET will have an entry in the datasheet for Rds(on). This is the on-resistance. In that entry it will list
one or more gate voltages (Vgs) together with the on-resistance at that drive level.
That's it.
Provide that voltage between gate and source, it will conduct with that on-resistance.
Give zero volts between gate and source it will be off, leaking a few microamps at most.
From the load current and on-resistance you can calculate the on-voltage, IR, and the on-power I^2R,
so long as the on-voltage is small (under a volt) and the on-power isn't going to overheat the package
or heatsink, you're good.
Ignore everything except this and the max voltage ratings.
Threshold voltage confuses a lot of people. Ignore it.
The max current rating is not practical, ignore it.
If the on-resistance is only listed for 10V, its not going to work reliably at less than 10V. If the on resistance
is listed for 5V, 4.5V or less, its logic-level and can be driven by an Arduino pin.
MarkT:
MOSFET will have an entry in the datasheet for Rds(on). This is the on-resistance. In that entry it will list
one or more gate voltages (Vgs) together with the on-resistance at that drive level.That's it.
Provide that voltage between gate and source, it will conduct with that on-resistance.
Give zero volts between gate and source it will be off, leaking a few microamps at most.From the load current and on-resistance you can calculate the on-voltage, IR, and the on-power I^2R,
so long as the on-voltage is small (under a volt) and the on-power isn't going to overheat the package
or heatsink, you're good.Ignore everything except this and the max voltage ratings.
Threshold voltage confuses a lot of people. Ignore it.
The max current rating is not practical, ignore it.
If the on-resistance is only listed for 10V, its not going to work reliably at less than 10V. If the on resistance
is listed for 5V, 4.5V or less, its logic-level and can be driven by an Arduino pin.
Wow, I wish all my professors teached like you, plain and simple . Really helpful, thank you very much. Will try this tommorrow.
Okay, one last question, I bought IRLZ44N MOSFET, in my understanding it should be okay, its logic level, and all other specs are good. I tested it with my spare esp and it works fine.
So the question is, should I use a diode? I saw that some people use it and some don't, I read somewhere that it has built in diode, but I'am not sure, because running a dc motor can give spykes if voltage and I don't want to risk it
That should be fine, and you learned more than you would have done if we'd told you which to buy. I think the rated current is overkill, but really that's not important. I hope you bought at least 2.
Yes, you need the diode across the motor. Forward current 1A or more should be OK.
I saw that some people use it and some don't
Yes, that gets debated on here sometimes. If you use one and don't need it, no harm done. If you don't use one and do need it your MOSFET will end up in the bin.
It is also useful, but by no means essential, to put a 0μ1 capacitor across the motor as close as physically possible to reduce the electrical noise it generates.
Always use a free-wheel diode (or other snubbing circuit) with any inductive load such as motor, solenoid, relay, servo even... The alternative is high voltage spikes playing havoc with your switching devices and spraying EMI into other parts of the circuit.
Thats where I'll put the diode, is it correct way?