Ok To Use Tap Water/rain Water Mix?

[baron von bubba]

hi, i dont want to use RO water, mainly cos the expense.
i have a car port with plastic roof that'd be perfect to collect rain water, i'm thinking that i could use this to mix with my tap water.
reason for this is the tap water is fairly hard (10.7 dGH) and a ph of about 7.5 and also nitrates around 30ppm, which wouldnt be great for a planted tank would it?

thanks in advance for any opinions or thoughts!

 

[petertr]

Gh of 10 isn't too bad.

I use my tap water with Discus, and the Gh is 24 with a pH of 7.8 and I have no problems at all.



I also considered using a water-butt - but I was warned off it by people on here for various reasons:

1 - You don't know what is on your roof - bird ####, leaps to mind
2 - You don't know what is dissolved in the rain water on each day - a local fire, for instance
3 - You don't know what bugs get into your water butt

 

[three-fingers]

IMO it would really be a waste of time, that water sounds great for a planted tank - especially the yummy nitrates, which you will probably find disappear.

Even 'softwater' plants seem to do great in hardwater, you just need to get other actually important aspects right, mainly the balance between lighting, nutrients (including CO2) and sometimes water movement.

Websites that say hard water is bad for a planted tank are using outdated information, loads of people have fantastic planted tanks with very hard water these days.

With exception of maybe a few very delicate species, you should be able to grow most things with your water .

 

[BigC]

This is exactly what I did when breeding problematic rivulus sp.
75% rainwater collected from the fish house roof from clear corrugated sheeting into a rainwater butt filtered through carbon.
Only drawback being you need to live in an area with no heavy industry or this will polute the rainwater.
Regards
BigC

 

[nmonks]

Like BigC above, I use rainwater and tap water (50/50) all the time. It suits a wide variety of fish and gets great results from species that prefer water a bit softer than my local 20 degrees dH tap water. As BigC mentions, rainwater may be polluted if you live near a factory or some such. Otherwise carbon should filter out any slight impurities, though I confess, I rarely bother and haven't yet had problems. I do use water conditioner though, even though rainwater obviously won't have any chlorine in it.

Even allowing for some dust in the air, rainwater is a darn sight safer than tap water with regard to things like copper and chlorine and especially nitrate. Look at it this way: it rains into ponds, and yet no-one worries about the goldfish dying. So why would rainwater be any more harmful to your fish? You will need to clean the gutters on a regular basis though, otherwise you get a lot of leaves and moss in the butt, and as these rot, they lower the pH. Certain plastics might conceivably leach chemicals into the water, and some aquarists have recommended removing water from the butt and storing it in food-safe containers as soon as practical.

I agree with the other posters than 10 degrees dH water is ideal. Ignore the pH; repeat after me: pH doesn't matter, pH doesn't matter. All fish care about is [a] the dissolved minerals in the water and that the pH is stable. Take care of those two things, and you're laughing.

Cheers, Neale

 

[baron von bubba]

i should have put a poll up!
guess its like the heater cable debate!
tbh i'm supprised no one has yet said "you gotta have RO" :0)

so it seems i was worrying about my tap water for nothing then?