My fish keep dying!

[KatyInParadise]

My pond is attached to the back wall of our house.
We bought the house in Feb and the water was totally
Black. We drained it and cleaned it. It is a fountain falling into the small pond below which
Holds 260 gallons. I live in Key West, Fl so it never gets
really cold Or excessively hot (like in D. C. Right now).
About a month and a half ago we had a sudden hot spell causing
a massive algae bloom. Everything was green. Except for the
Oxygenating plants which all turned brown and died.
Started over. Pulled all the fish out. Muck-vacced the pond (which
Is cement bottom). Put in De-chlorinator, let it set for abt 2 days
(even though it says it works instantly), put fish in. All died except
For the algae eaters who stay on the bottom.
Now I have only three fish.
Test ammonia every day for week. It's always just
Barely at the "stress" level on the pkg color card.
Go to local fish store and ask what to do. Lady
Says should. E safe to introduce
Ore fish. So I buy fish. Before I add them i add API Ammo Lock and
Stress Coat. They are all dead today (even the Two new algae eaters)
Take water to pet store for THEM to test. Lady says all
Readings are within safe parameters. Hubby (who nothing abt ponds)
Thinks it's the concrete pieces I have my lilies perched on
HELP!!!

 

[Bali]

I have had a bad experience with putting "uncured" cement blocks in the pond. It may not be the sole cause of the fish deaths, but it would be a contributing factor to a low (and toxic) pH. I like PondCare products like EcoFix when there is first hint of an algae bloom. I also don't like to use products to rid a pond of chlorine. I will use a bit of aquarium salt if I have to, but I prefer to just let the pond sit for a couple of days (fountain on to aerate) and let the chlorine evaporate naturally. But these suggestions may not cover all of what happened. The fish looked fine when you took them OUT? Did you put them in a non -chlorine tank or holding pond? I sometimes use PondCare Stress Coat when I have to move my koi. I am really sorry to hear about your loss, and I hope I have not merely added more confusion. Good luck with the next guys.

 

[sissy]

not sure about your water but city water needs treated and you need a filter that can filter the water really well for at least a month or 2 .A pond does not do well in heat as it depletes the oxygen from the pond really fast .If your pond gets a lot of sun it can even be worse .Fish need oxygen and plants give it off during the day but plants also use up a lot of oxygen at night .

 

[buckry]

The fact that you are registering any ammonia at all in a brand new pond is kind of surprising. When you say you "buy fish" what does that mean? You're putting 50 cheap goldfish in. You're buying 10" koi? Some combination of those two? I have never gotten a positive reading for ammonia in either of my ponds and I only rarely get the tiniest little bit like .02ppm in my little aquarium, and usually that's only because it's only 20 gallons and can have up to 15 small fish in it at any given time.

If you're draining your pond and redoing it, ammonia should be zero for quite a while.

 

[Waterbug]

Number and size of fish in both die off cases? Amount of food fed? Water test results, numbers rather than "good", "fair", etc. How long were the fish back in the pond before they died? They all die on the same day?

Let me do some guessing. Bought the house in Feb. Cleaned pond in March? Month and a half ago algae bloom. So that's about 3 months before the bloom? I'm guessing there was a build up of ammonia during those 3 months and the bloom did you a huge favor by sucking up all the ammonia saving your fish. Just a guess.

The Ammo Lock converts chloramine (which I assume your city uses) into ammonia for one thing and also makes the ammonia safe to fish. Unfortunately your test for ammonia probably can't tell the difference. So a pond filled with chloramine treated water and Ammo Lock would indeed measure ammonia. There are specific test kits to tell safe ammonia from toxic ammonia. Even slight amounts of non-safe ammonia is a problem over long periods of time, so that could be a problem.

Don't worry about the concrete.

 

[crsublette]

Howdy Katey, welcome!! Don't fret! Pond is like a garden that can become over ran with weeds and nasty crawly things until ya learn how to properly manage it. Then, ponds becomes your own personal oasis.

It would be best if you could write out the test results the pet store told you. Even though the pet store clerk say everything is ok, it is best to get a second opinion on the test results. When you go to a doctor and found you have a life threatening condition, then often go to another doctor for a second opinion. It sounds like you are in this type of situation with your pond. The tests results are the vitals that we need to be read so your pond can be properly diagnosed just so you are not misguided ... too much.

At risk of becoming too technical ... My understanding is pH swings, ammonia and/or nitrite poisoning, or buying a bad batch of fish are the most common reasons for dead fish to new owners. Also tell the clerk that you used an ammonia chemical binder called API Ammo Lock and ask if their tests can give you the NH3 and NH4 values. Particular testing mediums will register ammonia binder chemicals as ammonia (the NH4 ammonium type). Normal ammonia tests combine both the NH3 and NH4 into a single test reading.

The concrete pieces might be ok. All concrete and cement is not made equally. Do these pieces crumble or flake easy? If so, then it might be a problem since there is no, or weak, natural seal. The cement used in concrete can sometimes have all sorts of lime and limestone composites. If this stuff is broken loose too much, then lime or limestone release compounds that can cause a pH swing. Like I said though, all concrete, cement, mortar are not made the same way ... You would really have to have some cheap stuff or cement from a few decades ago to have a problem. So you probably are ok.

Also ... Are you dumping the water in the fish bags from the store into the pond ?? don't do this if you are.

Do ya have a water softener or something that softens water to one particular spicket?? If so, was there a chance ya used this water? When ya say you pulled fish out and put back in, there might have been a big pH swing from one location to the other.

How many fish are we talking about ?? What is your best guess on the size of the fish ?? What type of fish, koi, comets, other ??

Also tell us more about your pond such as filters you use, if you use any. Pumps you use, if you use any.

Type out the test results for us!! along with more answers. It will help much !!

Save your money. I wouldn't go out buying stuff just due to the label saying "all natural" or label saying "it can do amazing things". I think ya did well with the Ammo Lock and Dechlorinator with the stress coat and taking the water to a store to test. Sounds like you are going right so far ... except for the dieing fish which is ok and good for your cats ((if they don't choke on the bones)) ... kidding!! The dieing fish will get fixed too.

If it becomes too much, then ya could put some fun looking plants in there and put in a black water dye. The dye will hide all the stuff going on in the water. Then do a couple more things to make sure the plants stay healthy and water does not become septic.

You just don't know what you got your self into now. Don't fret. It will all come together. Buy the house with a pond. You also bought your self a continuing hobby ... which can be fun once ya learn what's going on.

 

[In2deep]

If Im not mistaken cement and cement products contain lye which is extremely toxic to fish. You may need to drain the pond and seal the cement and other concrete products that are in there. I see clear water sealer everywhere.

 

[don't ask]

welcome
KatyInParadise

and sorry to hear of your troubles..i am no expert but i do know that cured concrete has a fairly high ph i think i recall double digits, which may be a source of the problem.. simple to just take out pieces and see what happens

 

[Waterbug]

PVC pipe is made with vinyl chloride which is highly toxic, flammable and a carcinogenic. How is that we use PVC for drinking water supplies? Because there is a difference between an ingredient and a final product that is the result of a reaction.

Same with concrete. One ingredient in concrete mix is hydroxide. Either sodium hydroxide (caustic soda or lye), or potassium hydroxide (caustic potash) or calcium hydroxide (slaked lime). Which ever one is used they are all very nasty. All would raise pH. But none of these exist in concrete. They exist in the bag of concrete mix before water is added. When water is added the ingredients becomes something else, concrete. Specifically slaked lime Ca(OH)2 becomes CaCO3 which is calcite. Calcite is used in water purification systems to rise water pH to 7.0 to 7.8. Not exactly dangerous levels.

Check out the #5 post by finse in the thread "installing a pump shut off switch, concrete question". He mixed up a bucket of concrete and tested the pH of the water right after mixing and it was 9. That's with no cured time, before the reaction was complete.

 

[Waterbug]

That was an over simplification. The hydroxide material does remain inside the concrete but doesn't doesn't leech out. It would only be released as the concrete dissolves over 100, 200 or whatever number of years it takes for concrete to dissolve.

The surface of fresh concrete is about 12 pH. Once placed in a body of water that surface pH dilutes to levels we can't measure with pond test kits. Which is why finse measured 7 pH when water was placed onto fresh concrete. If you just pour a tiny bit of water onto fresh concrete and lay a pH strip onto the concrete you can read 11 or 12 pH.

Once the calcite forms on the surface, in a process called carbonation, the pH of concrete is 7-8 pH. Meaning if you laid a test strip directly on the surface. Surface only.

It takes acid to dissolve concrete. If a person wanted to keep a pond at 5 or 6 pH the concrete would leech and very slowly, over years, raise the pH to 7 or 8. Concrete is a poor pH buffer for the same reason plaster of paris and whole oyster shells are poor pH buffers. If crushed into a power they would raise pH quickly, but they're solid and slow to dissolve.

 

[crsublette]

Everything I have read that increase in pH from concrete is extremely slight, sometimes does not even register, but false to say there is zero pH increase.

For ponds made completely out of concrete, no stones incorporated, then the pH may increase by a .5~1 pH point.

I also suppose there are different formulations where the calcite layer formed is very weak or nonexistent due to the hydration reaction process making porous or watertight dense concrete.

 

[Waterbug]

Concrete will definitely raise pH of water that's under 7. The higher the water pH the slower it would raise pH. But yeah, very slow. Pond normally head toward lower pH as acid is produced by decay, bacteria. So it would be very difficult (impossible imo) to measure any increase in pH in a pond. In a lab it could be done, has been done.

Over time the surface of concrete will react with CO2 in air or water and form calcite (calcium carbonate) which has a pH of 7. Called carbonation.

 

[crsublette]

Ok, awesome, thats what I was wondering. I thought something like that but wasn't for sure so didn't want to say anything. Good stuff. Thanks WB.

 

[KatyInParadise]

Thanks for all your helpful answers. I got a liquid pond testing set and it turns out that the pH was only 5.0, which probably was the contributing factor. Everything else tested within paramenters. I bought some pH Up but I have not been able to re-test the water as I have been ill. Will try to do that today. The only fish that are left in the pond are two beige algae eaters that stay on the bottom and I can't see them against the rocks! LOL Gonna test again and if all is well, will SLOWLY introduce fish again.

On the other hand, my water lilies are beginning to take off!

 

[Waterbug]

I would not trust that pH measurement. Lady at the pet store tested water and said everything was fine. I don't trust myself, pet store people, or really anyone when test results are strange. People make mistakes, test kits go bad. I always try to confirm results that are so far from a normal range. Vinegar has a pH of 5. To get that low of a pH someone would have to have dumped a lot of strong acid into the pond. The plant matter dying would release acid but not to this degree. And at 5 the cement bottom would be pushing pH higher, so really your pH would have been even lower at some point.

If you have some distilled water you can test its pH. If you don't get close to 7 you know your kit is bad.

There is also the possibility the pH is swinging up and down. The pet store could have tested an up swing and you tested a low point. Measuring KH provides more info than pH.

If you confirm low pH...Given the size of your pond, it might be better to remove the remaining fish, drain the pond and start over. There is not a lot of reason to add pH UP when you could just replace the water for a lot less $$$ and the result would be way better. Plus adding pH UP would increase pH quickly and most likely kill the remaining fish. In a tank you can slowly increase pH over days and save their lives.

You might want to Google "pond pH buffering". Could save you some additional trips to the fish store in the future.