Backyard Aquaponics
A place to discuss aquaponics

Based on the topic I posted last time, I tried out the Freshwater Master Test Kit to check out Nitrate level in my aquaponic system.


Please see my decided aquaponic system and scale. [DWC]
viewtopic.php?f=1&t=28701


After I carefully checked Nitrate, Ammonia, and pH level, these are the result:

- Nitrate level is approximately 20 ppm



- Ammonia level is approximately 0.25 ppm



- pH level is approximately 7.6

The question is what are the proper level of Nitrate, Ammonia, and pH in aquaponic system?
And what should I do to adjust them to stay in proper level?

Thank you for you help

If your system is past the initial cycling stage (ie: the initial 3-4 week period where you introduce an Ammonia source to the system to establish the beneficial bacteria colony), then your Ammonia reading should always be 0.0ppm in a balanced system.

A Nitrate level of 20.0ppm is perfectly fine, you will get very good plant growth at that level. In a well balanced system you can have a Nitrate level of 0.0ppm and still have healthy plant growth. A constant Nitrate level higher than 40ppm suggests a system doesn't have enough plants and/or has too many fish. At 80ppm, leafy greens, especially lettuce, will start to become bitter. At 160ppm it will inhibit seedling development, plant growth, fruit set etc, and can be harmful to fish long term.

A pH of 7.6 is fine. Don't try and fix what isn't broken. There will come a point in the future where it will start to drop naturally on it's own. When that time comes you try and catch it in the high 6's and maintain it there using small regular additions of products such as Calcium carbonate, Calcium Magnesium carbonate, Calcium hydroxide, and Potassium bicarbonate.

_________________
Mr Damage - a.k.a: Yabbies
Owner at Perth Aquaponics - Aquaponic Consultant & Trainer
Trade certified Horticulturist & Cert IV TAE

Thank you Mr. Damage.

Right at this time. I got very few plant in the system as it's in the stage of demonstration.
I wonder that the Nitrate level is quite low comparing to number of fish [500 ea] and number of plant [600 ea].
I afraid that if I raise the number of plant to 3,000 - 5,000 plant, it will be deficient of Nutrient

Do I need to worry about beneficial bacteria in the system, I have no idea that it colonizes and grows perfectly.

Here's my system scale:

- 7,870 gallons or 29,750 litter of water for the whole system
- 500 fishes
- 3,000 liter of water in fish tank
- 600 plants [20 days growth] [ Can be maximum at 5,000 plants in the future]

Thank you

Well you beat me to the reply so I'll just comment on the last part instead. You don't need to worry about the beneficial bacteria, they are pretty much everywhere and those local to you are probably better adapted to your area anyway.

Regarding the ammonia reading in that sample - sometimes you'll see a bump in the ammonia even in an established system. You probably are cycled but new systems are a bit less stable. Check to see if 0.25 is a toxic reading for your system water temp and pH --- http://ibcofaquaponics.com/information/tables-and-charts/