Water quality before it goes in the aquarium.

The science behind successful fishkeeping.
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Mito
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Couldn't think of another subject title! As I've said elsewhere I live in a very hard water area. I'm not connected to mains, water arrives via a lorry therefore expensive, the water coming from underground rivers. The last delivery had a hardness of 26Gdh. I have a RO unit which I use in the house for drinking water and cooking but it is wasteful of water. The waste water I use for plants occasionally. I was wondering if a water softener used in conjunction with RO would reduce the consumption of water. A LFS 20mins drive away will let me have RO water for free but I have to buy goods to qualify for the offer. There is a limit to what I can buy! A bit of a waffle but the grey matter is not functioning well in this heat. Around 35ºC all week.
LookoutTrout
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You clearly aren't in the UK so this may be a daft idea but can you harvest rain water?
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black ghost
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If I remember right he’s in Spain, but not on the plain where the rain falls, mainly. I think he’s in the arid sun-baked hills somewhere.

A domestic water softener will just replace the hardness with sodium, swapping one problem for another. It wouldn’t be great for fish.

The only solutions I can think of are... use RO, whether you make it yourself or buy it, or keep hard water fish (livebearers, Central American cichlids, Rift Valley cichlids)... or wait a couple of years till climate change turns Spain into a wet place.
I don't keep fish, I keep water. Water keeps fish.
Mito
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Thanks for the replies. Yes I live in Spain on the Costa Blanca but nowhere near Benidorm! I live about 6km from the sea at 300m above sea level. If anyone wants the coordinates of where I live , PM me. I was thinking that the hardness wouldn't change but might make for more efficient RO with less wastage. I think I'll stick with what I do unless the LFS changes is policy. I've looked into the possibility of chichlids but from what I can gather they are in general a stroppy lot. Isn't the water too hard for live bearers? Wouldn't I still need RO but presumably less of it?
walker26
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I have a water softener and an RO unit. My understanding is that running your water through a softener before the RO unit makes the membranes last longer, not sure it makes it more efficient though. I use a mixture of RO, tap and a little softened water to get the parameters where I want them, it’s a little bit of faffing about but works for me.

The sodium in softened water is minimal as the brine mixture is only used to rinse the ion exchange resin. That said, I realise that fish have a different biology to humans and are probably more sensitive, so wouldn’t use too much of it.

I’ve had no problems that I can relate to using a little softened water and have had Cories, Angels, Rams and Ottos breeding.
340 litre Aqua Oak
Fluval FX-4
Fluval Aquasky 2.0
Fluval Plant 3.0
Aquael Platinum 300W heater
4 x Angels (2 x breeding pairs)
6 x Gold Pristella Tetra
7 x Pristella Tetra
1 x Cardinal Tetra
1 x Female Rainbow Stiphodon Goby
8 x Sterbai Corys
6 x Ottocinclus
3 x Bristlenose
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black ghost
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walker26 wrote: Sat Aug 06, 2022 0:48 am
The sodium in softened water is minimal as the brine mixture is only used to rinse the ion exchange resin.
Not true. There is a brine mixture used to rinse the resin, but the resin itself is also charged with sodium. That’s how they work. Every calcium and magnesium ion removed is replaced with a sodium ion.
I don't keep fish, I keep water. Water keeps fish.
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I've looked at softeners a few times in the past and have never found a decent answer about how they change the water. I would expect if they didn't add anything to the water then companies selling them would be shouting it from the rooftops, that leaves me thinking they don't just soften water.
Mito
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An update and a question! I've installed a polyphosphate filter for the house. There is a noticeable difference in the water, less scale on the taps and cleaner glasses. The question is can this water be used in tanks, will it affect the fish? I don't think it will but I'd like other opinions.
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fr499y
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Depends entirely on what it uses to soften the water. Usually filters they remove limescale/soften water using certain salts are best avoided when doing water changes.

Do you have the make and model of the filter?
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black ghost
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Polyphosphate filters don’t add sodium so it should be ok to use.

They don’t soften water, they just prevent the ‘hardness’ from forming scale in the pipes, and dissolve scale that has already built up.
I don't keep fish, I keep water. Water keeps fish.
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