Any Ideas because I'm stumped

Discussion in 'pH' started by jdhef, Dec 22, 2012.

  1. jdhefModeratorModerator Member

    Okay, a little background. (Sorry for the length...hope you hang in till the end)

    Back before Halloween I had a mass die off in my 46 gallon Rainbow fish tank. When I tested the water I found nitrites were sky high, so I did a few back to back water changes to try to save the remaining fish.

    The nitrites zeroed back out, and since my bioload was reduced so much, I restocked the tank hoping to salvage the cycle. So the tank only had a reduced bio-load for about 3 days.

    After restocking, ammonia started to spike. So after about a week of daily water changes I added a bottle of SafeStart. On day 14 I test...I have elevated ammonia. So after about another week of water changes, I try SafeStart again. 14 days later I test...still have elevated ammonia, but fish seem fine.

    So on it goes with partial water changes a few times a week until today when I get the idea that maybe I have ammonium instead of ammonia (hence the ammonia being elevated, but fish do not seem effected). So I test my water and sure enough pH is about 6.0 at best. I test my tap water and the water in one of my betta tanks and it's above 7.6 (as is normally the case). I hadn't tested the goldfish tank or other betta tank since I had just done water changes on them, so I wouldn't get accurate results.

    So now I'm stumped as to why the 46 gallon tanks' pH keeps dropping. The only thing different between my 46 and the other tanks is that the 46 is pretty heavily aerated and has a UV filter.

    Anyone have any thoughs on whats going on with the pH?
  2. JessiNoel21Well Known MemberMember

    Any driftwood or leaves like Oak, Maple, or Indian Almond ?

  3. jdhefModeratorModerator Member

    Hey thanks for reading thru my post and to answer your

    And the tank has been set up quite a while. Origionally about 4 1/2 years ago I set up a 36 gallon, then back in Feb I upgraded to the 46. I reused the gravel (plus added 10 pounds of matching gravel), got a new cannister filter, but used the ceramic media from the 36 for an instant cycle. So in essence the tank has been set up for about 4 1/2 years with no problems.

  4. JessiNoel21Well Known MemberMember

    What water treatment do you use?

  5. QQQUUUUAADDDWell Known MemberMember

    What is the KH?
  6. JayseeFishlore LegendMember

    Wish I could help, but you know more about water chemistry stuff than I do...
  7. jdhefModeratorModerator Member

    I use NovAqua & Amquel+

    I do not know. I don't have a KH test kit, since it had never been a problem.

    I think you are just being modest!
  8. ryanrModeratorModerator Member

  9. JayseeFishlore LegendMember

    I wish that were true :) I think youre the first person to accuse me of modesty ;)

    Water chemistry is inconsequential to me though. I bought my first test kit this year, for experimentation purposes. I know ammonia, nitrite and nitrate. That's it.
  10. jdhefModeratorModerator Member

  11. jdhefModeratorModerator Member

    Okay, I got a GH/KH test kit and here are my results:

    Tap Water: 7 Drops KH and 4 Drops GH

    Tank Water 1 Drop KH and 4 Drops GH

    So not real sure on what this means, but I did buy some crushed coral, so I guess I'll put some in my cannister filter and see what happens. I'm not sure how quickly the crush coral works.
  12. ryanrModeratorModerator Member

    Ordinarily I'd suspect plants depleting carbonate in the absence of CO2, but given the tanks are not planted, that's ruled out.

    KH will eventually deplete itself in any setup, which is why PWC's help to maintain the buffer. How much water do you change? how often? It might be worth doing a few big water changes... 50% at a time, the KH in the tap water should bring things back to normal. And crushed coral will help stabilise it long term.

    I don't believe UV has any effect on pH/KH, certainly not in anything I've read about them.

    My only other guess (it's a long shot guess) is the aeration may promote too much gas exchange, resulting in too much carbonates being exchanged at the surface.... But this is a long shot guess.
  13. jdhefModeratorModerator Member

    Ryan, I change 25 gallons every Sunday morning. I too was thinking that it might be due to too much aeration, even though it seems unlikely.

    I attributed the mass die off I had back in October to the fact that my airstone broke during my Sunday water change and then when putting the spare airstone on the tubing, it also broke. I just stuck the airline in the tank figuring all would be well for a couple of days, until I gould get a new airstone, since in theory I shouldn't really even need one. But the next morning a awoke to find 6 of the 10 Rainbows dead. And as I mentioned earlier (sorry to repeat) when I tested the water I had 0ppm ammonia and off the chart nitrites. I had never though to check the pH.

    So I took off from work that day, got to PetSmart as soon as the opened and bought a pretty powerful air pump with a much larger airstone. There was definitly far more surface agitation than previously, but because I though my fish died because of a lack of aeration I figured more would be better. But maybe not.

    But I did a 20 gallon water change yesterday afternoon and put a valve on the airline to reduce the flow, but this morning pH was still 6.0 at best. (I guess it could be lower, but 6.0 is the bottom of the chart.)

    Hopefully the crushed coral will straighten this out. But I do have a question...does the coral at some point stop working and need to be replaced? Or does it slowly disolve and you just need to add more?

    Oh well...Thanks for bearing with me and being so helpful! I really do appriciate the help very much.
  14. jetajockeyFishlore VIPMember

    It dissolves over time.

    Does this tank with a KH problem have plants in it?
  15. ryanrModeratorModerator Member

    I believe it slowly dissolves away over time, and you just top it up. I don't use crushed coral so I'm just guessing, but makes sense to me.
  16. pirahnah3Fishlore VIPMember

    I am really thinking that you have a multi headed problem here. Somewhere along the way your tank has really taken a liking to sucking up alkalinity. Usually this is due to the biomass and is normally released after the nitrogen cycle. Where you had high nitrites in the tank it sounds like the alkalinity was depleated and then the pH started to drop drastically.

    You have to get that alkalinity back into the water to even hope to get a cycle going again. Personally I would use crushed coral in the long run of this and hope to be able to stop its use eventually but at the moment I would think of trying a pinch of baking soda in with a water change. Double check your pH in the bucket before adding thou just to be safe.

    I would do probably a 50% change and then around 8-10 hours after do a water change with the baking soda added, this should not spike the pH too badly but give you a really solid boost of alkalinity in the water which should kick your bacteria into high gear and get your cycle back and working again. I do have a feeling that you will have lost the cycle by now but there is always hope for it.
  17. catsma_97504Fishlore LegendMember

    There are only a few reasons I am aware of that cause a tank to become depleted of KH aka alkalinity.

    1. Housing live plants and not meeting their carbon needs
    2. A cycling or unstable tank
    3. Build up of debris and waste in the substrate which leads to an anaerobic situation
    4. Long term use of AmQuel+

    We can rule out the first one as you do not have live plants.

    We know that your tank is currently cycling and unstable. If this is the cause, it will be a temporary situation. Meaning once fully cycled and again stable the alkalinity will be released back into the water. Because of this you don't want to make too many changes now to end up with too much and shooting your pH into the opposite direction.

    When was the last time you did a deep gravel cleaning? Moved the decor around and cleaned underneath it? Could it be time for this? Tough call being as your tank is no longer cycled and stable.

    The last one may be a shocker. I have seen many threads where we determined that the use of AmQuel+ was the problem. In its chemical reaction to detox nitrogen it uses carbonate. The way to determine if this is the problem, knowing that your pH has crashed, I'd stop using it. Do a couple of daily water changes with only the NovAqua+ to see if it makes any difference in the KH and pH levels.

    Before attempting to add something to raise the KH levels, I'd let the fish be your guide. If they are not stressed, then I recommend only doing the daily water changes without using AmQuel+. But, if they ever do become stressed, using very small amounts of baking soda with a water change would do the trick. No more than 1/8 tsp per water change.

    Hopefully you will figure out what is going on in your tank and can gain control over it again.

    Keep us posted!
  18. jdhefModeratorModerator Member

    Thank you for answering and no, I do not have any live plants.

    I was kinda hoping you would take notic of this thread, since your in the water treatment business. Thanks for replying. I agree that I have lost my cycle, since I do have elevated ammonium. And I realize that as I start getting my pH back up I it's all going to start turning into ammonia. So it looks like there will be a bottle of SafeStart in my future.

    Thank you for taking the time on this...I know it's a busy time of year, so I really appriciate it.

    I do a pretty heavy gravel vac with every water change, so I shouldn't have any debis in the gravel, but I have been using Amquel+ for years now. And I usually overdose with it since I have nitrates in my tap water. This really seems to make the most sense. As we say in the engineering biz...Good Pickup!

    Sadly I have already put some crushed coral in my filter. Would you recommend removing it at this point and just going with the change in water conditioner (I'm going to pick up a bottle of Prime tomorrow assumng PetSmart is open) or would you recommend leaving the crushed coral in the filter since it's already there and changing water conditioners.
    Last edited by a moderator: Dec 23, 2012
  19. kinezumi89Fishlore VIPMember

    There was another member, blanking on her name, but she had a long-running thread discussing the same issue you're having, and the culprit ended up being Amquel+. That was going to be my guess, Dena beat me to it ;) I would change one variable at a time, starting with using Prime instead. I think Petsmart is open tomorrow. :) (They're still open now, technically ;))
  20. ryanrModeratorModerator Member


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