Keeping water clean in water tank

Rosy

when we arn't using our water tank i drain it completly and leave the filler open so air can get into it and keep the tank dry inside.never had any problems with the tank when i fill it next time.

cheers.

We've had our camper trailer with 40 L tank under, for 17 years. I just fill it up before we go away (hopefully a few times a year). I think I may have cleaned it out once in that time, just because it was out for another reason. The water in it appears OK, doesn't smell or taste funny, no floaties. I don't do anything special, our water doesn't have a use by date, it's great!

We do the opposite.

1) When returning from a trip, I drain all the water.
2) If during the trip we used non-tapwater (read non-chlorinated) then we fill up and drain again to clean out.
3) We then fill the tank to the brim leaving no air.

My theory is that the tapwater contains some chlorination and is better than leaving it with O2.

An emptied tank will always have a little water in it as it can never be completely drained; even dampness, when left, can then lead to mould.

My theory anyway, Never had a problem

Cheers, CJ

The thing with water tanks is that they are opaque and don't allow light to get to the water, this generally prevents anything like algae etc from growing, although I hear there are a few types that grow in the dark.

If the water is clean potable water when you put it in it should stay that way. I always empty and refill my tanks before I head off on a trip.

I fill with whatever water is available wherever we travel. Some is pretty smelly and hard, but we've never had any problems with gross contamination of the tank.

If you do notice lingering smells, you can try Bi carb soda to make it smell nice again, or if it's really bad about 250 mils household bleach in a full tank and let it soak overnight before draining it and flushing it out well.

Hi Rosy

Unless the water tank is clear and the sunlight can readily shine on it, you can leave the water in the tank for years. We do (after all, the rain just tops up the tank at home and can stay for years - or could in the good old days when it rained enough). We don't put water into the caravan tanks unless it passes the 'cup of tea taste test', and if need be, use water direct from a bucket if it is not good enough for our tanks. We have never needed to bleach our tanks or purify the water. We do not have a fancy filter for filling, but just use a food grade hose. A couple of times we have been caught with water that didn't taste good, and using the water and refilling was sufficient.

Motherhen

Thanks very much to everyone for their advice. I would say we will probably just keep it full of water from home while we are not using the camper. Didnt even think of the chlorine from home. That should keep it pure. We always fill it with potable water while away and have run out a couple of times but of course there is always some left in the tank.
Cheers Rosy

Provided the tank and all associated plumbing is not clear, then you can leave the water in the tank and just top up for the next trip.
Algae will only grow in the presence of light. If you happen to have any clear (food grade) plumbing - just lag it with loom tube and zip ties to prevent any light.

Water is a very precious commodity - don't waste it by simply draining and dumping.