Hi, newbie here. Just made a Harris pole, got a decent brush head, put two jets in and run a copper pipe along side. Will get photos when completed. Got an RO unit, a 1000l tank and a 350l tank for the car. Now, I have an issue, we are on metered water. How can I save money here? Water board say that we will have to go on a business tarrif and pay VAT on the whole lot. Someone on the web said they are legally obliged to put in another meter. We got a 5 stage RO plus a DI stage. We read my TDS and it is 157. Rain water off the roof, through the dirty gutters in an ancient water butt is 15 TDS. We are thinking of doing this. Is it viable to use rainwater? How long would straight DI last at 160 TDS and 15 TDS? Also, if I have used rain water and then stored the waste, could I put this back through as it would still be a low TDS? Cheers for this guys! Can't wait to get it sorted but it's being a tough journey!