Changing water supply to soft water?

[nurseshelly]

Hi,
We just got a water softener ... I'm wondering how I need to change my fish keeping habits to keep my loaches happy.
Can I use the softened water (it does use salt, but they say not very much) with the loaches, or not?
My previous pH was 6.8, which is not that alkaline, but we were having issues with calcium deposits at the water fixtures, water heater, and showers ... so it was hard.
So, are small, frequent, water changes safe until the majority of the tank water is the new, soft water? I don't want to do a major water change and shock my fish from pH or osmolality changes.
If I have to, I could get water from the back yard via a bucket to fill my tanks, and it would be the same water that the fish are accustomed to.
Michele

[Diana]

Test the KH, GH and TDS of the two water sources: Softened and un-softened. If the pH is already 6.8, then I would use the un-softened water. Fish can use the calcium in the water (GH) but cannot use the sodium (from the water softener) You may find that the TDS is lower in the unsoftened water, too. Soft water fish prefer a lower TDS.
See if your water softener will be OK if you use Potassium chloride. This is better for aquariums than sodium chloride.

[jones57742]

I'm wondering how I need to change my fish keeping habits to keep my loaches happy.

Yes!

Diana is correct but IMHO too moderate.

The concentration of NaCl and KCl which typical brands of water softeners employ will continually increase.

You can use outside faucet water, bypass the water softener internally or install a RO unit.

TR

[nurseshelly]

So, I tested the water ...

Tank:
pH 6.8
KH 2
GH more than 30 I gave up at that point!

"soft water" from my house tap (we have a water softener now, but apparently it's not that soft according to the GH). Oh, I'm not sure how accurate the pH is because I only let it sit 10 minutes before testing.
pH 7.8
KH 8
GH more than 30 I gave up at that point again.
Michele

[Diana]

Looks like something is removing the carbonates from the tank. Certain substrates will do this, and a few other things.

Let some water sit out overnight or longer and test the pH after 24-48 hours.

[Batch]

Looks like something is removing the carbonates from the tank. Certain substrates will do this, and a few other things.

Plants will "eat" the carbonates. In my heavily planted tanks, I have to add
it during most of the weekly water changes.

batch

[chefkeith]

Nitrifying bacteria also uses up kH.

One form of NTS and OTS, new and old tank syndrome, happens when the kH hits near zero, and then some of the nitrifying bacteria die off. Then a nitrite and/or ammonia spike follows. The pH also crashes. This sometimes happens to people who do fishless cycling, but also happens to old tanks.

Do you know what the Nitrate level is for the tank and tap? That would be important to know.

[jones57742]

"soft water" from my house tap (we have a water softener now, but apparently it's not that soft according to the GH). Oh, I'm not sure how accurate the pH is because I only let it sit 10 minutes before testing.
GH more than 30 I gave up at that point again.

ns:

If your shower soap is lathering up then you are within the definition of soft water per the water softener manufacturers.

Your water softener functions via the replacement of typically divalent elements with sodium and potassium, ie. salt water is being produced by your water softener.

Once again if you are using this "softened water" for WC's the salinity of your tank water is slowly but surely increasing due to evaporation of the tank water.

TR

[Diana]

Roughly half the plants used in aquariums will utilize carbonates as a source of carbon. This can VERY SLOWLY lower the KH in an aquarium. Most of my tanks are heavily planted but I have not noticed the KH dropping. KH in my tanks stays stable.

Decomposition and nitrification can remove the KH and is indeed part of Old Tank Syndrome. It takes a while, though, and a lack of water changes. Most tap water has enough KH to replace whatever is used by the decompoing organisms, and the nitrifying ones. Old Tank Syndrome shows up when the fishkeeper neglects the tank, does not do water changes.

Loss of KH can also happen when the tank is topped off with RO or Distilled water. The processes above are removing the carbonates, and RO or Distilled water has no carbonates to replace the carbonates removed.

On the other hand, ADA substrates and certain other ones can remove the KH at a noticeable rate. When I use Soil Master Select I need to monitor the KH pretty closely for about a year, until the SMS quits removing the carbonates from the water.