Backyard Aquaponics
A place to discuss aquaponics

My grow beds are approximately 80 cm x 40 cm with a 35 cm depth media. I am using a type of volcanic rock found locally as my media. I have no idea what my ammonia and nitrite levels are as I have no way to test for them. I would like to salt to 3ppm by am not sure what type of salt to use since aquarium salt is not available in my area, and I am not able to order on line. I am located in Amman, Jordan, with almost zero local knowledge of aquaponics. I would like to use regular un-iondized table salt. Any ideas?

Pool salt is what I use. Just make sure it has no additives.

I remember reading somewhere that you don't want to use table salt so I would stay away from that but maybe someone else could speak to that.

How many beds do you have that size?

I have three beds that size.

Thanks for the info aboman. I will try it out and post my results in this forum.

Based on your bed size I would also suggest reducing the number of fish to about 20 or so. This is especially true if you are unable to monitor your ammonia and nitrites.

Hope this is helpful. Good Luck!

Thanks aboman. I will get on it and see what happens.

Just a little update from me. I didn't salt after all , I know I've been meaning to do that and I will when I get a chance to go find and buy some salt. But all seems well and I've had no other casualties, the fish are all looking good and eating well etc. I've been keeping a close eye on the water parameters and IMO it's looking pretty good and fully cycled.

Recent water test results:
4/10/14 pm
Ammonia 0.25
Nitrite .125
Nitrate 10
PH 8

4/13/14 pm
Ammonia 0.50
Nitrite 0.1
Nitrate 20
PH 7.8

4/22/14 am
Ammonia 0.125
Nitrite 0
Nitrate 5.0
PH 7.625

Hey BDD, thanks for the update, but why do you have a fluctuation with the parameters? Have you taken measurements on variable times, ie. before feeding and/or after feeding?

@ kij2, Time of the day, feeding time and amount I feed them has all been inconsistent. I guess thats why but it looks in the safe zone so I thinks its OK.

Last reading:

2/27/14 pm
Ammonia 0.375
Nitrite 0.185
Nitrate 5.0
PH 6.75

I have three growbeds, 1.3 meters long, 0.7 meters wide, and 0.4 meters depths of media material, 0.35 is the depth of water.

I salted using an assumed volume of 600 liters and ended up salting to 12 ppt. Didn't have any instrumentation to measure, but then went out and bought a salinity stick and I found out I had salted to 12 ppt.

Immediately I changed out almost half the water and dropped the salinity to 4 ppt. It stayed at 12 ppt for almost a week.

Now the salinity is about 2.5 ppt, and has been for a few days. My plants suffered dramatically.

Also I think this affected the bacteria, I have been measuring ammonia, nitrite and nitrate and have been getting readings all over the place. My system is 6 weeks old and I have no idea what I am doing.

Ouch! Sorry to hear about this. I guess this will be one of those learning moments...

Yes, too much salt can harm your bio-filter and plants. I do not know what the specific threshold is though. It sounds like you may have found it... bummer... but don't worry they will return.

Couple of questions-
1. Have you lost anymore fish?
2. What are your latest readings?

I guess I have just jumped into this without doing enough research, lol.

To answer your questions:

1. No more fish have died.

2. Latest readings:

6/5/2014

Ammonia 0 - 0.25 ppm
Nitrite > 5.0 ppm
Nitrate 40.0 ppm
pH 8.14
Salinity 3.04 ppt
TDS 5.64 ppt
EC 5.67 ms

9/5/2014

Ammonia 0 - 0.25 ppm
Nitrite > 5.0 ppm
Nitrate 5.0 ppm
pH 7.77
Salinity 3.27 ppt
TDS 4.77 ppt
EC 5.93 ms

13/5/2014

Ammonia 0 - 0.25 ppm
Nitrite > 2.0 ppm
Nitrate 0.0 ppm
pH 8.23
Salinity 2.44 ppt
TDS 3.22 ppt
EC 4.66 ms

Thanks for the input.

I'm experiencing the same thing with my tilapia as well. Lost 3 in the past week with the same gross slimy residue on the fish. Before they died they were having issues swimming up right and just floated upside down. Did yours do the same?

I quarantined each fish and salted but I think they were too far gone. I read with the fungus & bacterial infections that you should disinfect the entire tank but that would destroy the beneficial bacteria.

Here is a picture, it looks almost like the fish is falling apart.

Wow, my problem was not nearly that problematic, I lost a total of 3 fish over 3 weeks. After salting the bejeezus out of the system (12 ppt, totally by accident, wanted only 3 ppt), over a period of 12 days, things got much better. I also did 30% water changes once a day for four days, I think what was causing it for me was the stress from ammonia and nitrite because my system wasn't cycled properly.

What are you parameters and reading over the last week?

first response was probably spot on, its merely a coating of saprolegnia fungus and bacteria that quickly starts infecting any dead fish. Leave them in the water for a week and they will be a fury ball.

That saprolegnia fungus sounds & looks about right. Makes sense too. I was feeding my fish every other day. I recently got married so I skipped a tank cleaning. (note: my aquaponics system is off line while I'm relocating so they are in aquariums with filters) So I'm not sure what the water parameters were as I just immediately started doing water changes.

I guess continual water changes and salt is the only thing to do. I read that hydrogen peroxide could be a solution but not sure of the amount.