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I can't keep fish alive anymore. It all started after I added a new small float bed using PVC liner and forgetting to turn off the tap hose and flooding my 180 gal system with too much chlorinated water. My fish were eating well that day and all died after 5 days. After cycling for 2 weeks, I added 10 more goldfish and all died within the next week, one or two per day. Never high ammonia levels and pH is around 6.9 to 7.1 with a temp of 72. Will a total water change now be enough? Can styrofoam or PVC liners be toxic? Could I have something bad in my grow beds, which are filled with expanded clay pellets?

I would love some help.

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you say "pvc liner"... can you be more specific? is it a food safe liner?  also, what kind of styrofoam? 

replacing all your water with chlorinated water likely re-set your biofilter.. it may take a while before you're cycled back up..

 

Hi len,

What exactly do you mean by "After cycling for 2 weeks"?

Before jumping to conclusions about polystyrene, or pliable PVC liner (which is never a good idea IMO, but not because of fish kills) mysterious 'bad' stuff' in the grow beds, or defective 'clay pellets'...how 'bout posting some very basic yet infinitely helpful info...like your water quality parameters (NH4/3, NO2, NO3) amount of bio-filtration, how long the system has been running or cycling etc...exact numbers are always nice...Since statements like "never high" can have wildly different meanings for different people, and so, are totally meaningless...

I'm going to assume that you are cycling with fish   ...Since adding fish 2 weeks into fish-less cycling would be just plain stupid...

Hi Len and Vlad. I feel your pain. I have been in the fish pond business for 20 years now and was totally amazed on how many fish I killed when I first started my AP system. I install huge Koi ponds and goldfish ponds every day as my day job, so I naturally decided to use gold fish for our first system. In my daily business, you couldn't kill gold fish unless you really did something crazy. They are so very hardy and can withstand the worst conditions. Well I killed 120 gold fish right away! I was so heart broken and in total disbelief. I checked my PH..7.0...perfect...ammonia...almost zero...nitrites, nitrates... everything was perfect...but everyday, one or two more fish were floating in my pond. This went on for 2 months until almost all the fish were dead. I did everything from drain my pond and remove all the fish into isolation tanks and tried in vain to save them, they all had the blood red blotches all under there bellies and around there gills. Technically called Hemorrhagic Septicemia. After chatting with TC lynxs, she ultimately was right in that I (a) added way to many fish for my new start up system and (b) you just got to get through you 90 day (approx. 3 months) "set up time" for your media beds or which ever system you have. I know it sounds crazy, but sure enough, exactly 90 days later, everything settled down. Fish stopped dying, plants started growing, the water in my fish pond became crystal clear. What I learned is this; start with a few small, cheap gold fish (and your going to loose some) monitor all the basic water conditions like PH, ammonia, nitrite, and nitrates. And last...just get through your 90 days. eventually, it will settle down and all will be fine...Greg McCord

I ran the water through the grow beds for two weeks prior to replacing the fish.  I checked for ammonia and added if levels disappeared.



Harold Sukhbir said:

Hi len,

What exactly do you mean by "After cycling for 2 weeks"?

Hi,  I cycled my system first without fish, adding ammonia and wated until nitrates were at 40ppm, nitrites dropped down to where I wasn't measuring them and ammonia was less than 0.25ppm. the pH was 6.93-7.0 and temp was at 72 degrees.  I then added fish and they did very well for about 4weeks.  They were eating and doing well.  Then I added a float system to experiment with that and I used a PVC liner material (my plumming already was made up of PVC pipe) because I thought it would be ok and I added water to the system.  I intended to only as small amounts at a time to account for the extra water needed to float my rafts.  I was distracted and actually flooded my 150 gal. tank and probably added 50 to 100 gals by the time I saw what had happened.  All the fish died and after two weeks of cycling the water through the grow beds I added fish again.  The amonnia was less than 0.25ppm at that time and pH by then was at or about 7.  The next patch of fish died one at a time over the next week.   I've changed all the water and have started over again by adding ammonia to raise the level to 4ppm. Also added liquid seaweed to fertilize the plants for now.

Vlad Jovanovic said:

Before jumping to conclusions about polystyrene, or pliable PVC liner (which is never a good idea IMO, but not because of fish kills) mysterious 'bad' stuff' in the grow beds, or defective 'clay pellets'...how 'bout posting some very basic yet infinitely helpful info...like your water quality parameters (NH4/3, NO2, NO3) amount of bio-filtration, how long the system has been running or cycling etc...exact numbers are always nice...Since statements like "never high" can have wildly different meanings for different people, and so, are totally meaningless...

I'm going to assume that you are cycling with fish   ...Since adding fish 2 weeks into fish-less cycling would be just plain stupid...

Hi Len,

Ok...........a chlorine kill, unfortunate but it happens to quite a few of us here. Glad you figured it out and are recycling as soon as possible. Some liners contain chemicals that can affect fish, so in the meantime(while cycling) you should get some background info on your particular liner and get that float working!

I guess that explains the first kill, but what about the second , I thought the chlorine would be gone after two weeks running the water through the grow beds?

Where is your nitrite (NO2) level at?

Hi Vlad,  The nitrite level was very low and not measurable using the water tester kit.  The color was at the 0ppm level.  I thought there would always be some nitrites, but after they peaked, they dropped to 0 while the nitrates continued to climb to around 40ppm.  Through out all this,  my nitrates have continued to stay at 40ppm or higher.  I almost makes me think the bacteria in the grow media didn't die like the fish.  Thanks, len
 
Vlad Jovanovic said:

Where is your nitrite (NO2) level at?

Ok then, nitrites seem kosher.  Any metal valves or pipes in the system? Copper, zinc (anything galvanized), brass? 

Now, everyone needs to do their own thinking/research and make their own decisions on the PVC liner front...but you really need to know that there is a HUGE difference in rigid PVC (like your pipes) and flexible PVC (like your liner).

In order to make PVC pliable and soft, a "chemical softener" must be added. These substances are called plasticizers. The most common plasticizers added to PVC in the United States have been banned in many other countries and continents. These plasticizers are called pthalates (BPA being one of the most problematic and unfortunately among the cheapest for industry to use...but there are others...DEHP, BBzP, DBP and a few more cheapies). These pthalates are quite toxic and have been linked to much nasty stuff...birth defects, various cancers, all sorts of freaky stuff...they fall into a category of toxins called hormone disrupters, which is a particularly nasty type of toxic...

To gist of the problem when using these products lies in that, on an atomic or molecular level, there does not exist (nor can there because of the nature of the substance) a covalent bond between the PVC and the pthalate plasticizer. So the chemical bond is a very weak one. Since it's so weak, the pthalate leaches out from the PVC and makes it's way through various vectors, into our blood streams, biological systems, AP water etc...Vinyl (which is what most folks call pliable PVC, is a horrible material...both because of it's crappy mechanical properties, and because of all the toxicity issues which surround it. But that is why it is so inexpensive...It's 'cheap' all around)...

Now, I am not saying (at all) that, that is what is killing your fish...might be, might not be...but that's not the point...

Just giving you a heads up so that if you wish, you can look into the matter yourself and make an informed decision about whether you wish to keep that liner in a re-circulating food production system for you and your Family. Since now that you're aware of the difference between rigid PVC and flexible PVC, you may wish to fork over the couple bucks for a good quality plastic (non-vinyl) liner like LDPE (low density polyethylene) such as the one 20mil liner that DuraSkrim makes. (I see that they've recently started marketing it as "Aquaponics Liner"...good marketing move on their part)...

With this info, it makes good sense to change the liner to something like the duraSkrim product. No metal parts in the system. Maybe instead of a small raft system I will use towers. Totally avoid the whole problem. Thanks for the info. If in fact there is some chemical leaching this early on, I wonder if it has contaminated the grow media and this needs complete changing as well. This could be very expensive to fix; a completely new system

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