Yen Yus

John C Daley wrote:What do you mean by 'self filtering' ?

How can you help the tank to clean the itself?

John C Daley wrote:What do you mean by 'self filtering' ?

How can you help the tank to clean the itself?

We have flush toilets that go to a vermifilter. We use around 4000 liters a month at the moment. We can top it off with water from the municipality.

What is needed for the tank to be self filtering?

John C Daley wrote:50 tons may be the weight of the tank, but not its volume.
The best way to settle and clean water us to have a large tank.
Filters etc are not needed if the tank is big.
350mm is low rainfall, how big is your family?

I would think about having thefirst flush be captured in another tank to be used in an orderly manner, with such low rainfall.

Sorry I meant 50 metric tonnes which is 50 m3. We have 4 occupants currently.

John C Daley wrote:How big is you tank and what rainfall do you get

The tank is around 50 tons (concrete tank). Rainfall is around 350 mm per year on average.

John C Daley wrote:Where did the 80 L figure come from ?
Do you have lots of dust, trees, bird poo?
Some diverts have spirals  or cyclones so less water is dumped.

Hi

0.5 liters per sqm. We have alot of dust around here because of tractors. I thought I'd have to clean the top layer at least before it enters the tank. I think I have solved the problem, I'm going to replace the 4 inch downpipe with a 6 inch which should give me 90 liters of storage. I will use that in the garden. The question is, how much filtering do I need to use the remaining water to take showers and wash dishes?

Hello

My roof area is 150 m2. So this means I would need about 80 liters first flush. My downpipe from the roof is 4 inch diameter and 5.7 meters long and the volume is 45 liters. How can I double my first flush? I don't have space for another pipe next to it.

I'm thinking how I can incorporate a sand filter in my design. Do you know of any good resources that tell you how to build and use one?

Thank you for your extensive reply.
Can you point me to a drawing or diagram for a first flush with two 90 degree at the top. Are the 90 degrees in a "U" shape?

Thank you for all your kind replies. We have already built an underground concrete tank which has a capacity of 50 tons (50000 liters). We have around 140 sqm roof space which we will use to collects the water.

There will be a first flush system in the form of a T pipe where the first flush side ( a 6 meter long 4 inch pipe) will fill and then carry on to a 2000 liter water tank which will be filled from the bottom up. Only the water that reaches the top will continue on to the main 50 ton tank.

Now I'm not sure how to treat the water in our main tank. The main tank will be connected to our home for showers, washing dishes etc. Everything other than drinking. Drinking water will be filtered with reverse osmosis.

Should I put chlorine in the main 50 ton tank to make it safe?
How should I design the first filter? Should I put a ball in the pipe so it can block of the pipe going down so when it fills it can continue to the other 2 ton tank?