Added aquaponics ibc tanks to existing pond


Joined
Nov 18, 2020
Messages
13
Reaction score
0
Country
Australia
Hi all,

I have had a 3000 litre koi pond in my back yard for about 5 years now, about 4 weeks ago I added 2x aquaponic grow beds above 750 litre ibc tanks which circulate water from the koi pond into the grow beds.

I was experiencing slow plant growth so I added some more fingerlings to the aquaponics (I now have about 55) and the koi pond has about 12 koi and gold fish in there things seem to be speeding up as I have been boosting/supplementing the aquaponics with my own urine.

I have been keeping and eye on the levels and the last few days my ammonia has gone to .5ppm but nitrite and nitrate are 0ppm, do you think adding the extra water, media plants etc has given my system a cycle crash? And it's now starting again or could it be that I didn't have enough beneficial bacteria in my pond and its not yet colonised my aquaponic grow beds?

Any help or theories would be much appreciated !
 
Ad

Advertisements

Joined
Oct 28, 2013
Messages
10,180
Reaction score
10,544
Location
Northern IL
Showcase(s):
1
Welcome to the GPF!

Is your goal growing things aquaponically? Or is your primary goal healthy fish? Because quite honestly your pond is WAAAAAY too small for that many fish, most especially koi. Even with your two aquaponic systems you are at barely 1000 gallons US. That's big enough for ONE koi.

Sorry to be the bearer of bad news - it's a common theme here on the GPF. And yes, I know - five year old pond, everything has been fine... until suddenly it won't be. You're seeing an ammonia spike - that's the first sign that you may have reached the tipping point. While everything else in your system stays the same, your fish continue to get bigger. Waste production increases exponentially. Increased filtration will help, but there are definitely limits that you simply cannot overcome.

I'd suggest you start re-homing some of the big fish. You'd be fine with goldfish. Oh, and stop peeing in the pond. ;)

We'd love to see photos of your set up by the way!
 
Joined
Nov 18, 2020
Messages
13
Reaction score
0
Country
Australia
Hi Lisak1,

I will definitely post some photos tomorrow when its day time!! (from Western Australia)

I have about 3 koi 30cm and the rest are goldfish and 2 koi fingerlings. they seem happy even though the pond might be a little small (roughly 9m x 1.5m x 0.4m)

What has been odd to me is that I have not registered any nitrite or nitrate in my system just the small spike in ammonia? which is possibly coz I have been over feeding and peeing in the pond to register some nitrate as fertiliser for the vegetables im growing?
 
Ad

Advertisements

Joined
Oct 4, 2019
Messages
235
Reaction score
130
Location
Winchester, VA
Hardiness Zone
6b
Country
United States
I was thinking you may have had a pH crash and that the water was acidic, killing the beneficial bacteria. That doesn't seem to be the case right now, but a pH of 7.0 doesn't give you much cushion. The nitrogen cycle constantly produces acid, so there needs to be some buffer, KH (alkalinity), to keep it from dropping into the acidic zone. I use baking soda to keep my KH up.

Hard water won't kill the bacteria.
 
Joined
Nov 18, 2020
Messages
13
Reaction score
0
Country
Australia
Could it be the sudden shock to the system (new fingerlings, pee and volume of water) and that the quantity of bacteria hasn't caught up? Am I correct in saying that the amount of bacteria in the pond is subject to load on the system/pond??
 
Joined
Oct 4, 2019
Messages
235
Reaction score
130
Location
Winchester, VA
Hardiness Zone
6b
Country
United States
If there is an established bacterial colony, it will catch up very quickly if there is sufficient surface for it to grow on. Under ideal conditions, temperature, food supply, pH, etc., it can double in 20 minutes. You don't want to keep overwhelming it, as it seems to be at this point. Stop peeing in the water and see how long it takes to catch up. It may be that you need to add more filtration, or at least more media for the necessary additional bacteria to grow on.
 
Joined
Nov 18, 2020
Messages
13
Reaction score
0
Country
Australia
If there is an established bacterial colony, it will catch up very quickly if there is sufficient surface for it to grow on. Under ideal conditions, temperature, food supply, pH, etc., it can double in 20 minutes. You don't want to keep overwhelming it, as it seems to be at this point. Stop peeing in the water and see how long it takes to catch up. It may be that you need to add more filtration, or at least more media for the necessary additional bacteria to grow on.
Thanks for your time in replying, I will definitely stop peeing it and keep track. If the pee is throwing it over the ammonia should clear in a day or 2? And can I please ask your thoughts on why I am getting zero nitrite and nitrate??
 
Ad

Advertisements

Joined
Oct 4, 2019
Messages
235
Reaction score
130
Location
Winchester, VA
Hardiness Zone
6b
Country
United States
How long it will take the bacteria to catch up depends on those factors I mentioned before. That many fish will provide more than enough ammonia for the bacteria to live on and grow, if it has sufficient places to do that and the proper environment.

You could have had a pH crash at some point, killing the beneficial bacteria. So your pond is no longer cycled. It looks to me as though it needs to go through that process again to get established. That's my guess.

Or it may be that by peeing in the water you are constantly adding more and more ammonia and the system doesn't have a chance to catch up. Maybe it will be able to stabilize itself if you just let it be.

If I were you, I would get some Prime or Safe, both made by Seachem, one a liquid and the other a powder. It will bind the ammonia and keep it from harming the fish. It will last only 48 hours for that purpose, so it needs to be done regularly until the pond is cycled. Water changes will also help keep those number down. I would also test for KH and boost that if and when needed.

I'm certainly no expert, so that's Just my two cents worth.
 
Joined
Nov 18, 2020
Messages
13
Reaction score
0
Country
Australia
I
How long it will take the bacteria to catch up depends on those factors I mentioned before. That many fish will provide more than enough ammonia for the bacteria to live on and grow, if it has sufficient places to do that and the proper environment.

You could have had a pH crash at some point, killing the beneficial bacteria. So your pond is no longer cycled. It looks to me as though it needs to go through that process again to get established. That's my guess.

Or it may be that by peeing in the water you are constantly adding more and more ammonia and the system doesn't have a chance to catch up. Maybe it will be able to stabilize itself if you just let it be.

If I were you, I would get some Prime or Safe, both made by Seachem, one a liquid and the other a powder. It will bind the ammonia and keep it from harming the fish. It will last only 48 hours for that purpose, so it needs to be done regularly until the pond is cycled. Water changes will also help keep those number down. I would also test for KH and boost that if and when needed.

I'm certainly no expert, so that's Just my two cents worth.
Will definitely look into the products you mentioned. Thanks again for your time i really appreciate it!
 
Joined
Oct 4, 2019
Messages
235
Reaction score
130
Location
Winchester, VA
Hardiness Zone
6b
Country
United States
You are very welcome. I hope your pond is sorted out soon and that your fish and plants thrive.

Best of luck.
 
Ad

Advertisements

Joined
Nov 18, 2020
Messages
13
Reaction score
0
Country
Australia
After doing some more research and investigating in the pond i found 1 dead fingerling and some uneaten food, if this were to contribute to the small ammonia spike, why would I not be seeing nitrite aswell?
 
Joined
Oct 4, 2019
Messages
235
Reaction score
130
Location
Winchester, VA
Hardiness Zone
6b
Country
United States
To me, that would be more evidence that you have no beneficial bacteria. There seems to be a lack of bacteria to convert the ammonia to nitrite.

For some reason the bacteria has died off and your pond needs to cycle again.

Maybe someone else has another idea, but I think you have lost your bacterial colony.
 
Joined
Nov 18, 2020
Messages
13
Reaction score
0
Country
Australia
Something odd is definitely happening i have another aquaponic tank cycling (separateto the system in question), I have added a handful of fish feed. And a few dead yabbies and in 2 weeks I have no sign of cycling starting!?
 
Ad

Advertisements

Joined
Oct 4, 2019
Messages
235
Reaction score
130
Location
Winchester, VA
Hardiness Zone
6b
Country
United States
Is there any ammonia showing up? It can take several weeks for the nitrogen cycle to be completed. I've not had one to get established in less than 2 months.

Low pH and low KH will definitely slow or even inhibit the process, as will low temperatures.

Are you using liquid testing kits? The strips are really not accurate enough to be of much use.
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Top