Water pipeline for water backfeeding and irrigation

It's me again with an update. After the on-site meeting with the garden and landscape gardener and pool builder regarding the connections, both recommended I use a cistern for the garden irrigation. I don't think that's a bad idea either. Especially since the pool builder is currently developing a filter to remove the chlorine from the water and thus be able to direct the weekly backwash into the cistern. However, the connection to the rainwater shaft is quite complex. Two meters deep have to be excavated over 10 meters. I received the price today for a [Graf XL Zisterne] made of plastic, including delivery, installation, and connection for just under €10,000. I find that really steep ...? Does anyone have an assessment? I actually have no desire or experience with the connection as a DIY job.

You can lead the backwash water directly into the cistern. The chlorine is immediately neutralized. No filter is needed for that… pure money-making. There are plenty of tests showing that this is not a problem with the low chlorine amount. We also have a cistern from Graf (76,000 liters). Can only report positive things.

You can lead the backwash water directly into the cistern. The chlorine is immediately neutralized.
No filter is needed for that… pure money-making.
There are plenty of tests proving that this is no problem at such a low chlorine concentration.
We also have a cistern from Graf (76,000 liters). Can only report positives.

Thanks for the quick feedback. It’s practical that you also have one from Graf. For us, the garden landscaper would install the 10,000 l version. Don’t you find that a bit expensive? So just under €10,000 including installation, connection, etc.?

The size of your cistern is, of course, impressive :). Just instinctively, I was leaning more towards concrete. What convinced you of a plastic tank? Or what about the operation of the Graf tank gives you a positive impression?

To protect the pool builder, I have to say he only mentioned it briefly and was proud that it’s quite a simple filter which, if it works as planned, is not expensive and can be equipped by yourself. But if I don’t need it, even better. By what or how is the chlorine neutralized?

The chlorine is neutralized when it comes into contact with dirt, soil, water… The concentration in a pool is so low that this happens immediately. Backwash water contains less chlorine because the dirt from the filter has already reacted with it.

The plastic cistern from Graf is well thought out. Proper pre-filter with flushing function, telescopic dome shaft for height adjustment.
Concrete tends to leak more easily.

€10,000 is not excessive for earthworks, installation, and the cistern. Is the filter included as well? The transport alone costs quite a bit.
You know yourself that everything is becoming and has become more expensive.
Production of plastic granulate, injection molding, logistics, etc.
Also, with 10,000 liters you have a larger cistern than the usual 5-7 thousand liters.

: We're starting next week. The cistern is ordered and all the holes for the connections are drilled. Now I'm taking care of the material for the irrigation. I ended up at DVS Beregnung. There are several levels like eco, premium, and expert. Do you happen to have experience with how to assess this? Is it worth going for the highest level? Or are the simple or middle parts sufficient? I'm having a hard time figuring out exactly what this means for me.

Take the middle level. Is sufficiently durable.