PPM/ PH/ Water Softening - Whats yours?

@Reedfish,

Hi Frank -

The hardness issue with fish has to do with the fish's ability to Osmo regulate.
Simply put-a fish will always try to maintain a higher level of minerals in its body, relevant to the minerals/salts dissolved inside the water column.
Fish can absorb these essentials via food and via the water column, and regulate this balance by increasing/decreasing "pure water" in its body via osmosis.
In other words, in harder water the fish can either increase its absorbtion of these minerals, or it can release (osmotically) water which thus increases the ppm balance of the contained water in its body.
Now, soft water fish need to be kept in soft water in order for easy osmo-regulation. The harder the water, the more "dehydrated" the fish need to be in order to maintain a higher than water column level of internal balance.
On the other side of the coin, fish such as malawis are used to high levels of internal minerals/salts, and a lower level of "hydration".
When kept in soft water, (to a certain level, as its easier for hard water fish to live in soft water than vice versa) the fish over "hydrates" and struggles to keep internal balance with the minerals then highly dissolved.

Kh, which is made up of bicarbonates mostly - is thus not on its own "worse" for fish, it forms part of the gh issue as explained above.
There are however fish that do not take kindly to high levels of kh specifically, such as some specific Amazonian species. (Altum angels, Heckel discus)
When fish are referred to though as soft water fish, it is generally accepted to refer to gh levels.

Does this answer your question?

Rgds

Marco

 

@Marco I've heard allot that soft water fish( such as wild caught Cardinal tetras) when kept in hard water " se nierre verkalk" sorry not sure how to put it in english
Is this true?

 

@nicolaas

Hehe-I dont know about that hey.
The basic concept is that with freshwater fish you have this continuous influx of water into their system, and for soft water fish kept in hard water, it basically boils down to them struggling to maintain that internal balance, as the water column keeps being higher in tds than what they can adapt to internally.
Its much easier for hard water fish, as the water will not be "pushing" them as such,as their natural state is that of a higher level than "normal".

In marine fish you have the opposite effect. Marine fish live in hard water, and they have this constant outflow of water from their system to get the body to adapt. This is why salt water fish constantly consume water, where freshwater fish dont.

I just want to add that this explanation is basic in nature. Im not a biologist or veterinarian, so terms and explanations are basic and just to give a broad understanding of why water hardness is important. Dont stone me if a better explanation is found.

Rgds

Marco

 

Hehe don't worry we wound stone you Marco, as far as I know we'd like you to stay alive for now

Thanks for the explanation I appreciate it.

Regards Francois