Water filtering

nathane

Active member
Hi folks,

I'm planning on incorporating a famous water filter system with the small bio-filter to give safe drinkable water into my build.

I'm trying to work out what I should be filtering. Do you filter just your cold drinking water after the offtake for your water heaters and non drinking applications, do you filter all cold after the offtake for the heater or do you filter everything.

In a small unit like I'm planning I'm thinking that I should just filter the cold kitchen sink drinking tap as the hot will be "brewed" at roughly 75 degrees in a calorifier, we can brush teeth in the kitchen and I don't drink much shower water! Benefit will be filter life and less pressure drop for the shower.

I guess we could run a debris filter on everything and a BIO filter on drinking as a compromise.

However I'm interested to know what most other folks do.

Let me know what you do

Thanks

Nathan
 

Joe917

Explorer
We use 2 10" filters, 5 micron particle followed by a 0.5micron carbon block. We filter all water. Any suspect, non-municipal water gets a 10 micron pre-filter and added chlorine in the tank. The carbon block removes the chlorine. 6 months between filter changes, full time use.
Pre filtering and reverse osmosis is the best option.
 

Badmiker

Member
We use 2 10" filters, 5 micron particle followed by a 0.5micron carbon block. We filter all water. Any suspect, non-municipal water gets a 10 micron pre-filter and added chlorine in the tank. The carbon block removes the chlorine. 6 months between filter changes, full time use.
Pre filtering and reverse osmosis is the best option.

We have a RO system under our kitchen sink as the water here in Shanghai is not safe to drink. How much 'waste' water would an RO use in a EX vehicle? Would you use a filter for the whole rig and an RO for the kitchen? Or RO the whole truck? The later seems ... time consuming, our RO could not do 100L/day.
 
Most people get filtered and purified mixed up. Filtered does not mean safe to drink or cook with, consider it gray water. Purified is safe for drinking or cooking, consider it fresh water. Filtered will only remove particles. RO and UV will eliminate and kill viruses and germs. RO will remove unknown chemicals.

I have been giving thought to some type of system to allow me to fill fresh water tank from any unknown fresh water source. RO is the best way to go but like said waste is a problem especially if you have limited supply. So if I have an external pump to fill the system why not place a sediment filter and a 5 micron filter plus an RO system before the water goes into the fresh water tank. Just make sure your waste from the RO goes downstream of where you are pumping from. You would need 40 to 60 psi to make the RO work properly. A dual or triple diaphragm RO will do 150 gallons per day a minute. No rush to fill fresh water holding tank, have all day. I want to keep whole camper system clean.
https://www.freshwatersystems.com/p...rse-osmosis-system-150gpd-w-booster-pump.aspx
Don't need the booster pump or tank in the above system.

For extra insurance can always add a UV system with a carbon filter after. Carbon type filter should always go after as they increase the TDS ( Total Dissolved Solids). UV system work best the lower the TDS is. I would add the UV system in the camper fresh water system and the TDS system in the fresh water fill system.

Speaking of TDS it would not hurt to add a TDS monitor to your system as you fill it. Helps to diagnose problem and monitoring of filter efficiency.

For those asking about califorer or water heaters. You water to filter before you heat any water. It will help prolong the life of your device.

TL/DR: Why do I want to put contaminated water into my camper system and then filter it. Better to purify before putting it into camper.
You can live a lot longer without food but no water will kill sooner. Water is your life blood.
 

carbon60

Explorer
Filtered does not mean safe to drink or cook with, consider it gray water. Purified is safe for drinking or cooking, consider it fresh water. Filtered will only remove particles. RO and UV will eliminate and kill viruses and germs. RO will remove unknown chemicals.

Leaving aside unknown chemicals, a 0.02 micron absolute pore size filter will do very well and is super cheap. Why get too crazy?
 

nathane

Active member
Thanks for input folks. I will look into reverse osmosis.

For load distribution reasons I'm planning on using two 170l fresh water tanks. I had originally thought I would place the filter post tank pre circuit, but this has me thinking maybe going with the filter between tanks and either filling the post filter tank from certain purity sources (e.g. travel in Europe) or time permitting via the pre filter tank and the filter. This would increase the complexity of the pumping system and introduce a second pump and float switch i think but has the benefit of pre filtering everything without affecting flow rates and pressures.

The filter I am looking at has a 0.2 micron filter which is described as suitable for removing bacterial pathogens.

I guess this maybe still leaves a risk of viral contamination. Would UV deal with this?

Keep the thoughts coming they are super helpful
 

moosevan

New member
I wouldn't drink reverse osmosis water long-term since it removes most of the minerals. I've seen Seagull IV recommended a few times with a prefilter and carbon filter.
 

Joe917

Explorer
I wouldn't drink reverse osmosis water long-term since it removes most of the minerals. I've seen Seagull IV recommended a few times with a prefilter and carbon filter.
It removes the minerals, so? You get minerals in your food, you do not need mineral water.
 
Yes mineral stripping does happen in RO water. That is its' major downfall. It will strip any minerals from you water system such as copper and iron and iron and magnesium from your body. You should supplement your mineral intake to correct this.

Thanks for input folks. I will look into reverse osmosis.

For load distribution reasons I'm planning on using two 170l fresh water tanks. I had originally thought I would place the filter post tank pre circuit, but this has me thinking maybe going with the filter between tanks and either filling the post filter tank from certain purity sources (e.g. travel in Europe) or time permitting via the pre filter tank and the filter. This would increase the complexity of the pumping system and introduce a second pump and float switch i think but has the benefit of pre filtering everything without affecting flow rates and pressures.

The filter I am looking at has a 0.2 micron filter which is described as suitable for removing bacterial pathogens.

I guess this maybe still leaves a risk of viral contamination. Would UV deal with this?

Keep the thoughts coming they are super helpful

0.1 would be better at removing the bacteria and yes UV would kill the critters but the water must be clean for the UV to be effective. Also you need a sediment filter before the 0.1 or 0.2 filter or you will get short lifetime use from the filter.

If you want to be simple and low maintenance then use a Berkey Filter for drinking and cooking and just gently chlorinate the shower water. (Very very little bleach in the shower water would kill the critters)
www.berkeyfilters.com

I am not a fan of Berkey Filters. I think for what they do and how they filter they are overrated. Berkey will not publish data on their filter effectiveness.
Their filter is mainly a charcoal or ceramic and charcoal filter. Does nothing more than just remove the sediment from the water and improve the taste. It will not remove bacteria and viruses. Some say it uses Silver to purify the water. This is Bull as there is no actual proof that silver is effective.

If you want simple and easy to use in a compact package check out Sawyer line of filters. Yes they have mostly turned to personal use filters like water bottles and they center around hikers. They still produce their 0.1 and 0.02 filters. These filters can be used either in a gravity drip type setup or a pressure usage. They can filter 170 gallons a day in a gravity system. The mistake most users make with Sawyer filters is they must be primed with water before use. RTFD is important before using Sawyer filters. Read The Friggin Directions

Here is what the Sawyer 0.02 can do for you:
With its 0.02 micron absolution filtration, the Point ZeroTwo goes one step beyond Sawyer’s MINI and Point ONE filters to remove 99.997% of viruses in addition to 99.99999% of bacteria and 99.9999% of protozoa/cysts.

One thing I do that helps extend filter life when drawing water from streams is use cheap coffee filters covering the end of the pickup. You would be surprised how much garbage this removes before it reaches the filter. Some have reported using women's panty hose as a prefilter. I have a hard time explaining to the wife on why I need panty hose.
 

Badmiker

Member
I would RO the kitchen water only, if you go that route. 100l a day is huge consumption, we do an easy month with 700l. We have a washing machine and a composting toilet.
Where are you planning to travel?
Good info here: https://www.rvwaterfilterstore.com/LRNCTR.htm
Sorry, I should have been clearer. We don't use 100l per day but if we were to fill our holding tank of ~ 400 (for example) using a RO that only flows 400l/day would result in taking a full day to fill your system.

I agree on using a combination of filters for application. Our house water is safe enough to brush our teeth, wash our bodies, do our cleaning of clothes and dishes etc, but for cooking and drinking we use the RO. Ours has a mineral addition phase that is after the membrane and holding tank. It then flows through a mineral filter to re-introduce trace elements. At least that is what the brochure said. Who knows?

So, pre filter -> filter -> holding tank with UV -> house use -> RO for kitchen. Whole rig clean water/ kitchen use drinkable water. That the basic idea? We could drain the waste RO water to either the 'clean' holding tank or a 'pre grey' for toilet/other use.
 
I would not want the RO waste to come in contact with me period. Consider it a highly concentrated biohazard but you can dump it right back into the water source you took it from. If it came from it, it can go back in it.
 

nathane

Active member

Forum statistics

Threads
185,535
Messages
2,875,628
Members
224,922
Latest member
Randy Towles
Top