Our village water pressure is getting stupid low, so it's time for a tank and pump. Single story, 2 bathrooms, 3 people. I've read thru some of these threads and see constant water pressure could be a problem.

Since I'm starting from scratch, what would be a good combination size of water tank and pump?

Having a well dug is the best source, even though it can go low during dry season. A 2000 liter tank is fine for most use.I use a Hitachi which has been good for the 7 years I've used it, with one pressure switch and hydrogen tank being replaced. Mitsubishi's are also good pumps. You can have both village water and a well, if you use different intakes to that water tank. This is from AI but explains more.................

Crucial Safety Notice: Never directly connect (cross-connect) a private well to a municipal water supply. Doing so can allow non-potable well water to flow backward into the public water supply, which is illegal and poses significant health risks to the community. 

Here is how to properly manage dual water sources:

1. Proper Plumbing Setup (The "How-To") 

• Physical Separation: The two systems should be separated by a manual valve (like a ball valve) or an automatic, certified 3-way valve. Only one source should be open at a time.

• Backflow Prevention: If you have both, the municipality will likely require you to install a testable, approved Reduced Pressure Zone (RPZ) backflow preventer to protect their pipes from your well water.

• Common Setup: Many homeowners keep the well for irrigation or outdoor use, and use municipal water for the house.

• Switching Method: You can install a dual supply kit with a three-way actuated valve that can switch water sourcing. 

29 minutes ago, fredwiggy said:

Having a well dug is the best source, even though it can go low during dry season. A 2000 liter tank is fine for most use.I use a Hitachi which has been good for the 7 years I've used it, with one pressure switch and hydrogen tank being replaced. Mitsubishi's are also good pumps. You can have both village water and a well, if you use different intakes to that water tank. This is from AI but explains more.................

Crucial Safety Notice: Never directly connect (cross-connect) a private well to a municipal water supply. Doing so can allow non-potable well water to flow backward into the public water supply, which is illegal and poses significant health risks to the community. 

Here is how to properly manage dual water sources:

1. Proper Plumbing Setup (The "How-To") 

• Physical Separation: The two systems should be separated by a manual valve (like a ball valve) or an automatic, certified 3-way valve. Only one source should be open at a time.

• Backflow Prevention: If you have both, the municipality will likely require you to install a testable, approved Reduced Pressure Zone (RPZ) backflow preventer to protect their pipes from your well water.

• Common Setup: Many homeowners keep the well for irrigation or outdoor use, and use municipal water for the house.

• Switching Method: You can install a dual supply kit with a three-way actuated valve that can switch water sourcing. 

We only have village water. I'll check out the size of 2000L tank. Then it's the right sized pump and inverter or constant flow. Just by reading I'm leaning towards the inverter type pump.

I found a 3,000 liter tank was marginally more expensive than 2,000 liter on Lazada.

Just show the staff this at any larger DIY shop. Home Pro, Global etc

“ต้องการชุดแทงค์น้ำต่อจากน้ำหมู่บ้าน ใช้ลูกลอย 1 นิ้ว เติมแทงค์ แล้วใช้ปั๊มน้ำอัตโนมัติ 200 วัตต์จ่ายเข้าบ้าน พร้อมบอลวาล์ว เช็ควาล์ว และกรองตะกอน”

“We need a water tank setup connected to the village water supply, using a 1-inch float valve to fill the tank, then a 200-watt automatic water pump to send water into the house, together with ball valves, a check valve, and a sediment filter.”

And they will make you a package, deliver and set up for you. If you do not need filter, then just tell them so

Check your daily water use then go for a tank around twice that. For most 1-2000L would be more than adequate.

For single storey one of the smaller Hitachi / Misubishi pumps would do the trick, there are cheaper Chinese units but they can be a bit noisy. If you have the $$$ then Grundfoss are the gold standard and very quiet, ours has been going fine since 2011 (replaced the pressure tank and capacitor[twice]) .

9 minutes ago, Hummin said:

Just show the staff this at any larger DIY shop. Home Pro, Global etc

“ต้องการชุดแทงค์น้ำต่อจากน้ำหมู่บ้าน ใช้ลูกลอย 1 นิ้ว เติมแทงค์ แล้วใช้ปั๊มน้ำอัตโนมัติ 200 วัตต์จ่ายเข้าบ้าน พร้อมบอลวาล์ว เช็ควาล์ว และกรองตะกอน”

“We need a water tank setup connected to the village water supply, using a 1-inch float valve to fill the tank, then a 200-watt automatic water pump to send water into the house, together with ball valves, a check valve, and a sediment filter.”

And they will make you a package, deliver and set up for you. If you do not need filter, then just tell them so

Our water supply can be spotty at times when they do maintenance, water turns brownish. I wouldn't mind a filter system leading to the water tank.

Is that how it's usually done?

12 minutes ago, Crossy said:

Check your daily water use then go for a tank around twice that. For most 1-2000L would be more than adequate.

For single storey one of the smaller Hitachi / Misubishi pumps would do the trick, but they can be a bit noisy. If you have the $$$ then Grundfoss are the gold standard, ours has been going fine since 2011 (replaced the pressure tank and capacitor[twice]) .

Sounds like a good way to figure out tank size. Will do.

8 minutes ago, EVENKEEL said:

Our water supply can be spotty at times when they do maintenance, water turns brownish. I wouldn't mind a filter system leading to the water tank.

Is that how it's usually done?

If you do not do it yourself with family or neighbours, or any handy man, yes,

1000L is more than enough for most families, but the larger tank, the more you got in reserve if water dissapear for a day or two. Hitachi or Mitsubishi pumps are decent priced and cant go wrong, or if you willing to pay a bit more, Crossy knows what he is talking about

1000 liter is more than enough for 3 people.

We have a fairly constant flow of village water and live with a 500 liter tank.

Buy a quality tank ("DOS", opaque) not the simple blue ones.

For a one storey house a 200W pump is plenty.

We have 255W and still good for shower and front loader washing machine in the upper floor.

Sure you can pay high for an inverter model with constant flow.

But we have a pump with a small pressure tank attached and all good.

Depending on location of the pump the on/off noise might be annoying.

Invest in some basic filtering before the tank.

At least a simple mesh and a 5 micron cartridge.

You will be astonished what you might find.

Worth mentioning, any handy man, doesnt mean he knows what he is doing, and if you do not know yourself, better let the DIY shop do the job for you.

You will need to build a «manifold» with stop valve, drain, vent, circulation if you want to add water treatment to the tank like we do, and also make sure the filter is placed after the pump, not before.

4 minutes ago, Hummin said:

and also make sure the filter is placed after the pump, not before.

We have both. Simple sediment filtering before the tank and a big filter after the tank to reduce lime (soften). This one needs regular care with backwashing and exchange resin every other year.

Tank and pump example (similar to ours).

9 minutes ago, KhunBENQ said:

We have both. Simple sediment filtering before the tank and a big filter after the tank to reduce lime (soften). This one needs regular care with backwashing and exchange resin every other year.

We backwashing every 3 months, change resin every year, but we do not have filter before the pump, is that normal set up instruction?

1 hour ago, EVENKEEL said:

I'm leaning towards the inverter type pump.

Lean away. Inverter sounds all tech and modern until you realize that water flow in a house is never constant it is on/off. So a regular Mitsubishi type pump is fine. Noisy? Not really. I

Single storey? You mean bungalow? Or is that a cultural misunderstanding on my part.

Install a spin-down filter before the tank, and a decent particle filter after the pump.

We have a 1,500 (750X2) storage on the ground floor and a 2,000l SS tank on the roof. It has always been enough for us.

If you have poor pressure/flow now, your water usage will likely go up significantly with good pressure/flow.

How much room do you have for the tank, and do you have a solid foundation for it?

Will you do the installation yourself?

4 hours ago, EVENKEEL said:

We only have village water. I'll check out the size of 2000L tank. Then it's the right sized pump and inverter or constant flow. Just by reading I'm leaning towards the inverter type pump.

Inverter is best, if you want really top quality look at Grundfos pumps.

As Crossy has pointed out, check your daily usage, also check frequency and time of no / interrupted supply, this will govern the tank size - too small doesn't really help you but oversized isn't any problem, plus it give time for settling of any rubbish coming in.

About Grundfos water pumps, I can certainly support the views expressed by Crossy and Artisi. I am currently using a Grundfos SCALA2 pump, which, while slightly more expensive than comparable models from Mitsubishi Electric and Hitachi, has proven to be exceptionally quiet and reliable, operating smoothly without any noticeable pressure fluctuations or “stuttering.”

Set up something like this: -

The non-return valve at the bottom provides a bypass of city water pressure if the pump (or power) fails so you at least have some water.

5 hours ago, Hummin said:

Worth mentioning, any handy man, doesnt mean he knows what he is doing, and if you do not know yourself, better let the DIY shop do the job for you.

You will need to build a «manifold» with stop valve, drain, vent, circulation if you want to add water treatment to the tank like we do, and also make sure the filter is placed after the pump, not before.

The only instance when you would place a filter after the pump is at point of use for drinkable water requirements, such as at your kitchen or bathroom sink area. Never install a filter directly after your pump! The filter will not work efficiently due to water being forced through it under pressure and once you open a tap you will lose system pressure due to the fact that the filter is creating a high resistance to water flow and a severe back pressure against the pump, thus preventing the pump from keeping the system pressurised. A filter works far more efficiently with minimal water pressure and a pressure pump works far more efficiently with minimal resistance to water flow. The best practice is to first connect your mains supply to a coarse 50-micron sediment pre-filter followed by a secondary 5-micron carbon filter ensuring clean potable water in your tank. This ensures your pump only handles clean filtered water extending its lifespan and is subject to minimal resistance ensuring when you open your taps the system remains pressurised. Like I mentioned, if you want to be 100% sure your water is safe to drink then install a point of use filtration system. As for pump models Hitachi and Mitsubishi are both okay, but Grunfos or DAB are far superior in performance, efficiency and build quality.

1 hour ago, Wotsup said:

The only instance when you would place a filter after the pump is at point of use for drinkable water requirements, such as at your kitchen or bathroom sink area. Never install a filter directly after your pump! The filter will not work efficiently due to water being forced through it under pressure and once you open a tap you will lose system pressure due to the fact that the filter is creating a high resistance to water flow and a severe back pressure against the pump, thus preventing the pump from keeping the system pressurised. A filter works far more efficiently with minimal water pressure and a pressure pump works far more efficiently with minimal resistance to water flow. The best practice is to first connect your mains supply to a coarse 50-micron sediment pre-filter followed by a secondary 5-micron carbon filter ensuring clean potable water in your tank. This ensures your pump only handles clean filtered water extending its lifespan and is subject to minimal resistance ensuring when you open your taps the system remains pressurised. Like I mentioned, if you want to be 100% sure your water is safe to drink then install a point of use filtration system. As for pump models Hitachi and Mitsubishi are both okay, but Grunfos or DAB are far superior in performance, efficiency and build quality.

I think you need to fact-check your claims first, because there is too much stated here as certainty from the outset.

You do not automatically need a coarse pre-filter if the tank is properly maintained and the water is coming from a municipal supply, though in some setups it can still be useful.

As for “never add a filter after the pump,” that is simply not correct. Many household filters are designed to operate on the pressurised side of the system, after the pump. And with a centrifugal pump like the Mitsubishi, a fine or restrictive filter is usually better on the outlet side, because too much restriction on the suction side can reduce inlet pressure and increase the risk of cavitation or priming problems.

Putting a carbon filter before a storage tank may remove chlorine residual before storage, which can be a water-quality disadvantage rather than an advantage.

I like a decent spin-down filter before the tank, and a particle filter or two after the pump.

I need to configure the pump and tank at our "new" place. I will used the exiting pump Mitsu EP405) and tank (2,000L DOS)

After the pump, I'll have a 50-micron pre-filter (and for the outside water) and a 5-micron secondary going into the house. If the 5-micron lasts a few months, I'll change it to a one.

I will also add a bladder accumulator after the filter to keep pump cycling at a minimum.

You do not want a filter that will starve your pump.

12 hours ago, Yellowtail said:

I like a decent spin-down filter before the tank, and a particle filter or two after the pump.

I need to configure the pump and tank at our "new" place. I will used the exiting pump Mitsu EP405) and tank (2,000L DOS)

After the pump, I'll have a 50-micron pre-filter (and for the outside water) and a 5-micron secondary going into the house. If the 5-micron lasts a few months, I'll change it to a one.

I will also add a bladder accumulator after the filter to keep pump cycling at a minimum.

You do not want a filter that will starve your pump.

I'll have a proper concrete slab poured for the tank. For us I'll assume a 1000L is good enough. I've seen a set up with the bladder tank. I'll just dive in and work out the kinks later 555

13 hours ago, Hummin said:

I think you need to fact-check your claims first, because there is too much stated here as certainty from the outset.

You do not automatically need a coarse pre-filter if the tank is properly maintained and the water is coming from a municipal supply, though in some setups it can still be useful.

As for “never add a filter after the pump,” that is simply not correct. Many household filters are designed to operate on the pressurised side of the system, after the pump. And with a centrifugal pump like the Mitsubishi, a fine or restrictive filter is usually better on the outlet side, because too much restriction on the suction side can reduce inlet pressure and increase the risk of cavitation or priming problems.

Putting a carbon filter before a storage tank may remove chlorine residual before storage, which can be a water-quality disadvantage rather than an advantage.

Our water is metered and when maintenance is done wherever the water can be brackish looking to the point you don't want to even shower with it. So definitely I'll have a filter before the tank. One after the tank is a maybe as we don't use tap water for anything but showers and dishes. But maybe a secondary filter would make me feel better about using tap water for washing veggies and such.

16 hours ago, Crossy said:

Set up something like this: -

The non-return valve at the bottom provides a bypass of city water pressure if the pump (or power) fails so you at least have some water.

Yes I'll definitely have a bypass line in case of malfunction. Thanks

It is good to have a service bypass fo filters.

12 minutes ago, EVENKEEL said:

Our water is metered and when maintenance is done wherever the water can be brackish looking to the point you don't want to even shower with it. So definitely I'll have a filter before the tank. One after the tank is a maybe as we don't use tap water for anything but showers and dishes. But maybe a secondary filter would make me feel better about using tap water for washing veggies and such.

Then this will help

coarse prefilter before tank

tank

Water treatment in tank

pump

finer sediment filter

And if needed, an activated carbon filter after the finer sediment filter can also help if the municipal chemical treatment is poorly controlled or overdosed, especially if you are adding further water treatment yourself. It can reduce chlorine, odours, and some chemical residues, making the water more comfortable for showering, brushing your teeth, washing up, and general household use.

We use this for our household water

Pro 5 Boxes of Water Purification Tablets, Hydrolyzed Top up Clear (Used for Water Purification Machines or Water Conditioning Tanks), Makes Water Clear and Clean, Reduces Fishy Odors, Eliminates Germs.

Need to buy the buoy separately

https://s.lazada.co.th/s.Z5lb9m

14 hours ago, Hummin said:

I think you need to fact-check your claims first, because there is too much stated here as certainty from the outset.

You do not automatically need a coarse pre-filter if the tank is properly maintained and the water is coming from a municipal supply, though in some setups it can still be useful.

As for “never add a filter after the pump,” that is simply not correct. Many household filters are designed to operate on the pressurised side of the system, after the pump. And with a centrifugal pump like the Mitsubishi, a fine or restrictive filter is usually better on the outlet side, because too much restriction on the suction side can reduce inlet pressure and increase the risk of cavitation or priming problems.

Putting a carbon filter before a storage tank may remove chlorine residual before storage, which can be a water-quality disadvantage rather than an advantage.

Ok, you know best!

1 hour ago, EVENKEEL said:

Yes I'll definitely have a bypass line in case of malfunction. Thanks

Take care with Crossy's bypass.

I would imagine he forgot the stop valve unless, of course, that strange looking check/non-return valve includes one.

I always thought the NRV symbol was similar to an electronic diode. You live and learn I guess.

1 hour ago, Muhendis said:

Take care with Crossy's bypass.

I would imagine he forgot the stop valve unless, of course, that strange looking check/non-return valve includes one.

I always thought the NRV symbol was similar to an electronic diode. You live and learn I guess.

Yeah, a valve between the pump and the check valve is great to have