Huge KH difference between LFS and home a problem for fish? Question

  1. lorianne621 Member Member

    I have been trying to stock some of my tanks with various tetras recently. I started with neon tetras with not so good results at first. I was very careful to slowly acclimate them and even though I knew they were not as hardy as I once thought I kept trying... I lost 60% the first batch, 90% the second batch...

    I wanted to get to the bottom of the problem. I began testing the water they came in and I discovered that my LFS is keeping them in our local tap water (more or less) and it is about as hard as you can get. The KH is off the scale on the API test kit and it takes about 20 drops to get the color to finally change. (I did this several times thinking I miscounted)

    Because of the hardwater issue, in my own tanks I use a mix of RO and Tap water... about a 5:1 ratio and the KH in my tanks will take about 6 drops to change color. The GH 5 to 7 depending on the tank...

    The PH holds steady at 8 in both my tanks and LFS... (weird huh?) I expected it to be different.

    Since that was the only difference I could find in the water... I made a hospital tank for my last group of neons and matched the KH to the LFS and then slowly over a period of days into weeks changed the KH to match the tank they were going into... I had a survival rate of 100%.

    I now have purchased both Serpae Tetras and Black Neon Tetras and I am trying the same process with them...

    Has anyone else noticed this kind of issue with huge differences between the KH at the LFS and what is in their own tanks... OR an issue with soft water fish having a low survival rate when kept in tanks with extremely hard water.

    I just wonder if I am on to something or if I just got lucky with the neons...
     
  2. ricmcc Well Known Member Member

    In that you already use a combination of RO/ Tap water, I would very slowly acclimate them to the value you wish--but very gradually, as they were doing alright in the hard water that your LFS has.
    A sudden change is far more lethal than any absolute value, so I really do stress making a gradual change.
    My point is the your LFS is maintaining them at parameters that you wish to change, yet they cannot possibly have a die off rate approaching 90%.
    So be very patient in changing their water parameters..
    Btw, a high KH will support a high Ph, but not vice versa.-best to you, rick
     

  3. DaniosRock Member Member

    I think you were very smart to figure out the KH connection. I would certainly encourage you to do the same with subsequent fish. I have seen issues with my own fish when our water softener was serviced and I did a 50% w/c the following day. They looked like they were having seizures. I tested the water and it had dropped by 6 drops. Apparently the softener had not been working well. All the fish survived but I did 5% w/c for almost 3 weeks before doing a 20%, 30%, 50% the 4th and 5th week. It was really hard to see them so stressed.
     
  4. Thai Aquarium owner Well Known Member Member

    The high Kh at LFS could be due to the place using only one large filtration system for all the species.
    This is a common practice to reduce costs and maintainance / staff.
    The filter will probably be run off the local tap water, a fact that you have already eluded to, but inside the filter there may be cost cutting media also.
    By cost cutting media, the filter may have some material inside that that will increase the Kh like maybe pumis stone or coral sticks instead of expensive ceramic rings.
    Sure it will hold BB the same, but the water parameters are all over the place, and due to the shop hopefully having a fast turn over of the fish, there is no real need to change things
    Just my 2 pennies worth
     

  5. lorianne621 Member Member

    Thanks for the input.

    I did as suggested and took 24 hours to slowly acclimate them over to a mix of RO and Tap water. The Ratio in the tank I put them in is only 50/50 but the KH is still significantly lower than the water they came. I could not match that high KH even if I wanted to. LOL
    They seem fine and unstressed. I did lose two of the Black Neon Tetras but 2 fish out of 15 is not bad...
    And just for the record.... this is the only time I have ever bought that many fish at one time... and I probably won't ever again... but they were all on sale for $1 each and all were in the same tank and going into the same large established tank. We will see how it goes...
     
  6. hampalong Fishlore VIP Member

    I buy fish from all over the place, including mail order.

    Mixing fish is usually taken for granted as a simple thing following the basic steps, but actually that only works if the two waters are fairly similar. No mention is made in most advice for drastically different pH, or worse still, hardness. In these cases it needs to take a long time, sometimes longer than the fish will cope with in a small bag.

    I'm sure many deaths of recently acquired fish are directly or indirectly caused by being mixed too quickly.