On Hardness Testing .....

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DeathStalker

Candiru
MFK Member
Apr 8, 2015
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United States
Hello all!

I recently switched substrate on the advice of my LFS (to CaribSea's African Cichlid gravel, small). My ph has typically been right around 7. Now it is up to ~7.8. However, in double-checking the safe ph ranges for my occupants (varying from eels, to Africa/SA Cichlids, Synos, and Plecos - and everyone is within "tolerance" range), I am more concerned about the hardness. I have *never* tested for this in the years I've been keeping fish. I'm wondering if it's something I truly need to be concerned about?

If so, will this TDH Tester satisfy the testing needs? (as opposed to strips) -

https://www.amazon.com/HM-Digital-TDS-EZ-Measurement-Resolution/dp/B002C0A7ZY/

Or is there something better to use?

Thanks! :)
 
Water hardness has a direct relations with Ph and its stability. But can I ask why you were prompted by your LFS to change to African cichlid substrate? Was it because you added Africans to your tank?
You have a mix of fish from different location and you may be within a "tolerance range" of Ph and hardness for all these fish, but its going to be very difficult to provide the best environment for all the fish if you just try to provide a "tolerance range".
I believe you would get better results and happier fish if you would separate the differing fish based on their individual needs.
 
I didn't add any new fish - same ones I've had for a while. I replaced the tank and stand (they were ~20yrs old) and that was what they recommended. I didn't realize it raised the ph. The water chemistry has stabilized - a bit of fluctuation with the new water and substrate for a few days, nitrite spikes, etc, but that has evened out. Ph is stable, no nitrites, no ammonia.
 
To get anal (which I do a lot). Certain fish belong in the same tank (same water chemistry, same temps, etc etc,) some don't.
1) Rift lake African cichlids, rift lake eels, and Central American cichlids and live bearers have evolved to in high pH (as high as 9) mineral rich (hard) water
2).Amazonian cichlids, tetras, Asia eels, etc have evolved to live in soft (7 falling to as low as 4pH) mineral poor waters.
Cichlids from west of the Andes neutral to harder pH, Gymnogeophagus and other Uruguayan (southern South America, barbs from China, etc etc require neutral water chemistry, and cooler water.
If you added the substrate for the first and 3rd group, a perfect situation.
If you have the 2nd group you may be taking those, out of their optimum range.
Many people will say "oh but after 2 or 3 generations in non-optimum water they will have adapted. As compared to 3 million years of evolution? To me that's a stretch.
It is always best to keep your fish in the optimum water conditions they had in nature.
Less than optimum, causes stress=disease etc etc. So if you keep fish from differing location that don't match, err on the side of more tanks than one.
 
With all due respect, all the information is fine and helpful, but my *central* question has never even been addressed - what is the most appropriate manner to test hardness and is the instrument I listed in the link appropriate?

Thanks.
 
With all due respect, all the information is fine and helpful, but my *central* question has never even been addressed - what is the most appropriate manner to test hardness and is the instrument I listed in the link appropriate?

Thanks.
Water hardness consists of 2 things. Carbonate hardness and general hardness. Carbonate hardness, or kh, is a measure of ph buffering capacity. The minerals, usually calcium carbonate, resist any changes in ph and keep the tank stable. General hardness, or gh, generally consist of the various salts that we find in our tap water. I.e. sodium, potassium, magnesium and calcium. These salts do not provide any buffering capacity, but are essential to the health of fish. Tds, or total dissolved solids, is a measurement of how well the tested water conducts electricity since pure h2o is non conductive and any dissolved minerals increase conductivity. The problem with measuring tds is it lumps everything together. Gh, kh, and even things like extra hydrogen ions. To me, a gh/kh test kit is the best way to actually measure hardness. I use a tds meter on one of my tanks, but that's only because the kh is below what is easily discernable with the test kit. Hope this helps.
 
Api gh kh test kit is what I use its cheap and fairly accurate.
With all due respect this does not address the fact that many of your fish are being subjected to the wrong conditions.
 
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