Rain Water

[Squidward]

Hi All,

So I have a water butt attached to one of the drainpipes off my roof.

The question is, can I use it in my tank?

I have done a bit of research online, but can't find anything conclusive. There are arguments for and against.
I have seen people say no, some people say it is ok as long as it is prefiltered through carbon first. And I have also read of someone useing raw rain water in their tank without pre-treatment

I live on the outskirts of greater London, more or less in the country.
Farms all around from the small villiage where I live.
No industrial area nearby. The M25 motorway is about a mile away.

My fish are soft water fish, so the softness is not an issue. I will prob mix it with some pre-treated tap water anyway.

But I don't want to poison my fish if the rain water has other contaminants.

Thanks

 

[DerpPH]

Use testing kits on the water, It is one way to find out, test the pH and kH and gH, And run it through a carbon filter. If you want to use it

 

[DrRob]

It can be done, the concern is atmospheric pollutants dissolving in the water.
 
There is a test that some use called the daphnia test, basically run a feeder tank of daphnia and put some in each bucket that you draw for water change. If the daphnia die, throw the contents of the water butt on the plants in the garden, not in the fish tank. Plus it makes for instant live food with every water change.
 
Problem is that you never know when a local farmer is going to spray the fields, or when a change in the air currents in the higher atmosphere will pull clouds from Heathrow over you to rain kerosene down onto you. Otherwise, rain water is a wonderful resource for soft water fish.

 

[TwoTankAmin]

It goes beyond the atmospheric pollution. How are you going to collect the rainwater? Most folks usually but a barrel under the outflow of agutter downspout from the gutter system on their roof. This uses the area of the roof to collect a much biger amount of water and funnel into one place. The problem is what it can pick up rolling down the tiles and through the gutters which contain who knows what. To deal with unwanted mold/fungus/lichen etc. it is common practice to use zinc strips we have them on out roof.0
 
Trace amounts of zinc are necessary for life, more is toxic. Its like copper. These are the kind of things of which one should be aware when using rain water. Of course chemical contaminents are one side of the potential problems. There is also the problem of unwanted solids. Color flakes from roof tiles, pieces of wood and bark, dead insects etc. etc.
 
This all doesn't mean one cannot make effective use of rain water, you just need to be mindful of the potential problems to avoid. If you live where it rains a lot the odds are many things are naturally washed off/out because of the regular rain.

 

[Ch4rlie]

TTA has just got there before me! lol
 
But his advice is pretty much the same as what was going to say anyway!
 
As you say, there is IMO, good and bad with using rainwater from a water butt.
 
First question for me would be, is there any pollutants or containments that rain water could collect from roof tiles, guttering, roof lead, and drainpipe?
Think if you have slate or natural stone tiles on roof then should be fine as there should be no pollutants from man made tiles
Is your guttering and drainpipe the plastic type, then that should probably be ok, but if its clay or worse asbestos pipe then hmm...
 
Next questions are to do with the water butt, the amount of dirt that can collect at the bottom of a water butt is almost staggering!
I used a water butt for watering plants in garden and was always careful not to drain water too close to bottom of the butt otherwise would disturb the silt/dirt at bottom. Might be possible this may not be so good for tank water? 
 
Also, as the water butt is outside and usually has a loose lid, all sorts of creatures can use the water for laying eggs, for example Damselfly or Dragonflies can lay eggs in this (especially if you live not too far form a pond or lake)
Trust me, you do NOT want damselfly nymphs or dragonfly larvae in your fish tank!
 
If you regularly clean the water butt and have a good closed lid and have plastic guttering and pipes, ok roof tiles, then I cannot see why not as long as you are careful and test the water before adding to tank.
Maybe adding carbon as you mentioned earlier might not be a bad idea as well (might be fairly costly in long run as active carbon only lasts a few weeks)
 
Not a bad idea but just be careful really and do a bit more research before deciding on whether to use natural rain water or not.
These suggestions are just off the top of my head and have not researched into this either so I could be totally wrong and someone might tell me off! lol

 

[hobby5]

During dry periods roofs can collect quite some dirt. So in an ideal case you would not collect the first rain, but let the first wave clean your roof and pipes and start collecting later. Also it is better to only collect after and during heavy rain, because this will certainly flush the system and any present contaminant will be much more diluted compared to collections during drizzles.

 

[TwoTankAmin]

There is a part of this we did not look at. I live where it rains enough that I could collect rain water should I so desire. I do not do this. I do own an RO/DI unit. I paid $100 for a 75 gpd portable unit and and yearly it costs me $50-$60 to replace the carbon cart and maybe the RO membrane. I make the water I need about every two weeks over a 24 hours period and store about 25 gals.
 
To buy barrels and other equipment and then to figure out how to move the rain water into the fish areas, how to insure it is safe to use etc. seems to me to be more time consuming and costly than my RO/DI unit. It certainly takes less time. The biggest difference is I never worry about contaminants, dirt etc. in my RO/DI water, I always would have a at least some doubt in the back of my mind regarding rain water.
 
My assumption here is that using rain and RO/DI water are similar in that they are either mixed with one's tap or reconstituted to some extent if used pure.
 
As an nteresting aside. 13 years ago when I put up my first tank my well water out of the tap was pH 7.4, GH 6dg and KH 5dg. Today they are a hair over 7.0, barely 5 dg and 4 dg. Same well just much bigger demands on the aquifer and water table. I believe the rain water no longer has the same contact time with the rock to pick up the minerals etc. it did before it gets used today. I discovered the change a few years back when a friend came over with her TDS meter and tested a few of my tanks. What should have been 105-120 ppm range was in the high 70s.

 

[Squidward]

I would go the RO route, but storage is a problem for me.
 
But I do worry about the quality of rain water.
The roof is "standard" tiles.
Guttering is plastic.

 

[thefishmesswithmywater]

There is a part of this we did not look at. I live where it rains enough that I could collect rain water should I so desire. I do not do this. I do own an RO/DI unit. I paid $100 for a 75 gpd portable unit and and yearly it costs me $50-$60 to replace the carbon cart and maybe the RO membrane. I make the water I need about every two weeks over a 24 hours period and store about 25 gals.
 
To buy barrels and other equipment and then to figure out how to move the rain water into the fish areas, how to insure it is safe to use etc. seems to me to be more time consuming and costly than my RO/DI unit. It certainly takes less time. The biggest difference is I never worry about contaminants, dirt etc. in my RO/DI water, I always would have a at least some doubt in the back of my mind regarding rain water.
 
My assumption here is that using rain and RO/DI water are similar in that they are either mixed with one's tap or reconstituted to some extent if used pure.
 
As an nteresting aside. 13 years ago when I put up my first tank my well water out of the tap was pH 7.4, GH 6dg and KH 5dg. Today they are a hair over 7.0, barely 5 dg and 4 dg. Same well just much bigger demands on the aquifer and water table. I believe the rain water no longer has the same contact time with the rock to pick up the minerals etc. it did before it gets used today. I discovered the change a few years back when a friend came over with her TDS meter and tested a few of my tanks. What should have been 105-120 ppm range was in the high 70s.

My husband is a greenkeeper at a golf course and he has seen a change in the levels of PH, GH and KH over the years as grass needs a balance to grow and as with fish knowing what your parameters are tells you what fish will be compatible, same with grass. The industry has just started to cotton on to the changes and are investigating and testing in earnest.
I think in a few years we may all be more aware about pollution and its very long term affects on water.

 

[Alasse]

I've used rainwater for a quite number of years, at my old house that was all i had access to. I drank it so cant see why my fish couldnt live in it. Unfortunately i dont have access to it at my new place, well until i can get the tank hooked up, once i do, i will be changing some tanks back to tank water only

 

[DrRob]

I would go the RO route, but storage is a problem for me.
 
But I do worry about the quality of rain water.
The roof is "standard" tiles.
Guttering is plastic.

 
Remove the guttering from the water butt. Run the RO to the water butt. Keep the lid tightly closed to keep wee beasties out. Storage problem solved.