Could London water supply be good for reef tank use?

[peterhos]

Good evening all. I have just been wondering. A few years back I stopped using a skimmer on a softie tank, retained the mechanical filtration and gave up using RO water. The corals in the tank took off and flourished until I took the tank apart to redecorate. Our London water supply is classified as ‘hard’. It contains chlorine at 1 ppm or less. I guess fluorine and aluminium may be present in similar small controlled quantities. Do you think a good quality hard water supply might even be good for the reef tank? Is it worth investigating? If yes it would save £££ and time and effort on water changes. Thanks in advance.

 

[thatmanMIKEson]

Good evening all. I have just been wondering. A few years back I stopped using a skimmer on a softie tank, retained the mechanical filtration and gave up using RO water. The corals in the tank took off and flourished until I took the tank apart to redecorate. Our London water supply is classified as ‘hard’. It contains chlorine at 1 ppm or less. I guess fluorine and aluminium may be present in similar small controlled quantities. Do you think a good quality hard water supply might even be good for the reef tank? Is it worth investigating? If yes it would save £££ and time and effort on water changes. Thanks in advance.

I would suggest to filter your water and if you want those elements in your water add them to better control the quantities and levels over time, its just a guess what's in any tapwater. If you start with ultra pure water you can add whatever you want in the quantities you want instead of relying on the tap.

If you want less work and cost I would continue doing what your doing if it's working, don't change a good thing.

 

[Randy Holmes-Farley]

Good evening all. I have just been wondering. A few years back I stopped using a skimmer on a softie tank, retained the mechanical filtration and gave up using RO water. The corals in the tank took off and flourished until I took the tank apart to redecorate. Our London water supply is classified as ‘hard’. It contains chlorine at 1 ppm or less. I guess fluorine and aluminium may be present in similar small controlled quantities. Do you think a good quality hard water supply might even be good for the reef tank? Is it worth investigating? If yes it would save £££ and time and effort on water changes. Thanks in advance.

Copper from your own pipes may be an issue, and many water supplies add silicate.

Does London supply a water analysis report?

 

[fishyjoes]

My tap water is also "hard" with alk around 7 dkh. I used that once to make saltwater up to 35ppt and ended up with nearly 20 dkh alk (I don't recall the exact number).
So I would advise not to use hard tap water for that reason alone.

 

[peterhos]

Copper from your own pipes may be an issue, and many water supplies add silicate.

Does London supply a water analysis report?

Yes it is easy to get a water report online. Is it easy to say something like ‘any heavy metals over 1 ppm is a bad thing’. Or are there different acceptable levels for different elements? What makes me think is how my softie tank too off visibly when I started using our hard tap water.

 

[Tired]

One of the problems with tap water is that the quality can change unexpectedly, in ways that are fine for humans but problematic for corals. A report that shows acceptable levels doesn't necessarily reflect what the water will be like in a month.

I would hazard a guess that your soft corals liked nutrients present in the water, which would be easy enough to replicate in RO water by simply not doing too many water changes.

Different elements have different acceptable levels, yes. Pretty much any detectable amount of copper will be an issue for invertebrates, for one, and that won't necessarily be in the water report- your own pipes, or pipes somewhere in your neighborhood, can add it after it leaves the source.

 

[peterhos]

Thank you all. As ever somewhere in all of this lies the ‘truth’. I am keen to end up with a nice tank full of SPS corals in due course. Having started with dry rock (live rock is prohibitively expensive or unavailable here) I wonder if the dry rock is leaching phosphate back into the tank. Quite a lot to think about all in all…