Aquaponic safe additives, nutrients, and chemicals.

Aquaponic system additives

Disclaimer

  • The inclusion of links from this wiki does not imply endorsements
  • Before purchasing and using any of chemical compounds listed on this page, care should be taken to check material safety data sheets ( MSDS ) and or manufacturer supplied directions for proper & safe handling.

  • Repeating, rephrased, you are solely responsible for your health and well being, some of the compounds below can be hazardous to yourself as well as to pets & others if improperly used and or improperly stored. Respect & obey the Material safety data sheets – MSDS, they are there to inform you of any risks involved in handling these compounds.

Overview

Once your AP system has matured, the main concern will be keeping your water more alkaline or PH buffered and raising it to be more basic as a living biolayer will tend to drift to being more acidic nitrification.org “Nitratation”, nitrification.org “pH effects of nitrification” . Below is a list of compounds that can be used to raise/lower PH, are used to maintain an AP system, and are generally safe/benign to fish and for human consumption.

Quick overview of PH, basicity & acidity, alkaline & acid.

Water treatment

An ongoing process is being able to replenish an Aquaponic system as water is lost through plant perspiration, evaporation, leaks, and harvesting of plants.

A crucial but not insurmountable problem is dealing with Chlorine & Chloramine.

Additional links
Ways to remove chloramine & chlorine – Home brew StackExchange answer *Note beer & wine brewing has problems similar to Aquaponics for initial water quality as both rely on bacterial ( or fungal ) processes.

Ascorbic Acid – Chloramine

Fact value
Common names Vitamin C
Chemical name C^6 H^8 O^6
Common state Generally sold in a liquid form.
Dosage Dependant on your local municipal water supplier’s annual quality report.
PH In 5% water solution, 2.2-2.5 ref

For systems without a water filter ( specifically an R/O – reverse osmosis filter with actived carbon filtration ) and using municipal or city water supply, chloramines can be problematic as its chlorine bonded to ammonium, making it resilient to normal dechlorination procedures. It can take weeks or months for a PH neutral 5 gallon bucket of chloramine treated water to become chloramine free.

Proper dosage relies on acquiring your local water suppliers annual water quality report where they “should” provide both a concentration level of chlorine/chloramine use along with trace minerals & elements in the water. Overdosing on ascorbic acid ( 5, 10, 20ml for a +100 liter ) from my experience ( zynix ) has not been a point of crisis.

Additional resources

Sodium Thiosulfate

Fact value
Chemical name Na2^ S^2 O^3
Common state Ideally sold as a liquid but can also be sold in crystalline form.
Dosage Similar to Ascorbic, check your municipal water supplies annual quality report.
PH 7- 9 in 30% solution ref

Note The presence of Na ( sodium ) can be problematic in Aquaponics because sodium remains in the system and slowly builds up over time. Q&A with Dr. Wilson Lennard – Q “You advocate NOT using…” – 1st sentence

Used for neutralizing both chlorine & chloramine from unfiltered municipal water supplies. How much is heavily dependant on the concentration/amount of chloramine and chlorine in the water needing to be treated.

Searches for FDA, EPA, OSHA, and other public record pertaining to Sodium Thiosulfate being toxic in short or long term came up empty. Absence of evidence does not make Sodium thiosulfate safe nor does it make it dangerous, it just means that there hasn’t been any interest and money to study the compound.

Additional resources

PH raising compounds

Potassium Hydroxide

Fact value
Common names Caustic potash, Potash lye, Potassia, Potassium hydrate
Chemical name KOH
Common state Odorless, white powder/ash

A somewhat caustic/hazardous material. It should only be used by someone well versed in chemical materials handling. The primary benefit is that this does not add more calcium to a system. That said; I, zynix/person writing this, am extremely uncomfortable with recommending acquiring/using this.

http://podcast.brightagrotech.com/episode-16-potassium-calcium-and-magnesium-in-aquaponics/

https://brightagrotech.leadpages.net/managing-potassium-deficiencies/

Wikipedia Entry

Calcium Carbonate

Fact value
Common names Limestone; calcite; aragonite; chalk
Chemical name CaCO^3
Common state Sold as a brownish to white powder
Dosage System/volume specific – use in small does 1x a day with testing to gauge appropriate amounts
PH 9.4 ( if saturated )ref

Primarily used to raise PH but also used as a way to provide calcium to an AP system, which is an important nutrient for plants.ref – “The Importance of Calcium”

Additionally the Carbonate part ( CO^3 ) will influence carbonate hardness and act as a Ph buffer ( slowing down how fast PH will fall to acidicity ). Wikipedia – Carbonate Hardness – 3rd paragraph

Additional resources

Wikipedia entry

MSDS entry – ScienceLab.com

Potassium Carbonate

Fact value
Common names Carbonate of potash, Dipotassium carbonate, Sub-carbonate of potash, Pearl ash, Potash, Salt of tartar, Salt of wormwood
Chemical name K^2 CO^3
Common state Sold as a white powder
Dosage System/volume specific – use in small does 1x a day with testing to gauge appropriate amounts

Primarily used to raise PH, secondary is that it provides a safe form of Potassium for plants.

Additional resources

/r/AP – “Potassium Carbonate and Calcium Carbonate or Potassium Hydroxide and Calcium Hydroxide? LOW pH Emergency”

PH lowering compounds

Phosphoric acid

Fact value
Common names orthophosphoric acid
Chemical name H^3 PO^4
Common state Diluted in water, clear and somewhat noxious smell
Dosage 18% is diluted enough not to cause immediate injury/burns. >=100ml amounts

Generally you do not want to use Phosphoric acid often or in large quantities in an established AP system. Prior to cycling, this can be used in moderation to lower PH and breakdown carbonate/KH.

Note Excessive use of Phosphoric acid can increase the chances of creating an Algae bloom wikipedia – Freshwater algal bloom

Additional resources

Wikipedia Entry

11 quick facts about phosphoric acid

MSDS – ScienceLab.com

Hydrochloric acid

Fact value
Status DO NOT RECOMMEND – NEED CITATIONS
Common names Muriatic acid, HCL
Chemical name HCL
Common state Liquid form/diluted or concentrate
Dosage Like all other acids, a little bit goes a long way. Use in >5ml ( for a +100 liter ) test amounts until you understand how much of an effect it will have on KH ( carbonate hardness ) and PH.

Hydrochloric acid is found naturally in gastric acid.
— Quoted from the wikipedia entry.

Abundant and cheap to procure ( look for hot tub/pool supply stores ).

Note Muriatic acid/Hydrochloric acid is sold in a variety of dilute amounts. If so motivated you can find very high concentration Muriatic acid for sale but then it becomes a lot easier to hurt yourself, your plants, your fish, and even your AP system. US wholesale stores generally sell Muriatic Acid at 15% concentrations. Not directly applicable to Aquaponics but in swimming pool care, 14 oz ( 414 ml ) of 15% concentrated Muriatic acid is enough to move Ph from 8.0 to 6.0 in a relatively short amount of time for a 250 gallon ( 950 liters ) tank of water.

Additional resources

Wikipedia Entry

Applications-> “ph Control and neutralization”

MSDS – Kem Tek 15% Muriatic acid solution

PH buffering compounds

Potassium Bicarbonate

Fact value
Chemical name KHCO^3
Common state Crystaline/powder
Dosage Similar to Sodium bicarbonate, a small amount goes a long way. Recommendations vary from 15mg per 1000 liters to 20mg per 1000 liter, adding 1x a day and then testing KH before adding more. Should only be needed 1x a month or 1x every other week depending on how much ammonia is being burned/converted into Nitrate.

Potassium Bicarbonate has dual benefits, it provides potassium to your plants and the Bicarbonate raises the KH ( carbonate hardness, alkalinity ) of the water. This is a preferred method of raising KH, especially over Baking soda as it does not
contain sodium.

Additional resources

Wikipedia Entry

Sodium bicarbonate (baking soda)

Fact value
Status Not recommend for continual maintenance due to sodium buildup.
Common names Baking Soda
Chemical name NaHCO^3
Common state Granular powder
Dosage Very small amounts ( >1gram ), will not raise/lower PH but slow down PH changes and difficult to remove once in.

Used to increase KH, a very small amount can go a long way.

Note The presence of Na ( sodium ) can be problematic in Aquaponics because sodium remains in the system and slowly builds up over time. Q&A with Dr. Wilson Lennard – Q “You advocate NOT using…” – 1st sentence

Wikipedia Entry

Egg shells/sea shells

Fact value
Common names Chicken egg shells & sea shells
Chemical name Calcium carbonate
Common state egg or shell state
Dosage I have not found firm citation of amount of shells to use, for my own systems I have 2-3 gram bags of shells resting adjacent to my bell siphon to ensure water flows over it.

IMPORTANT NOTE Before using egg shells in your AP system, to avoid poisoning your system with undesirable bacteria its recommended to boil the shells in water OR microwave them to sanitize. Salmonella destroying temperature & time is 10 minutes at 75C (167F).

Unlike other recommended compounds, egg & sea shells have the benefit of staying in your system 24/7 until they slowly dissolve away. Ideally this should take months if not a year or more to happen. During that time, if you imagine acidic PH like heating water, then by analogy shells are like an ice cube that slowly melts away keeping the heat ( or without analogy the PH up ).

Discussion on /r/AP about sea & egg shell use

Trace minerals

Magnesium

Magnesium sulfate (Epsom salt)

Fact value
Common names Epsom salt, English salt
Chemical name MgSO^4
Common state White Crystalline, powder forms.
Dosage Unfortunately the only way to gauge dosage is by watching plants to see if they have a Magnesium deficiency. 1x every other day until plants look healthier.

Food/fish safe in small amounts. The sulfate will lower PH so be prepared for that citation

Wikipedia Entry

Iron

Iron is a crucial and major supplement for Aquaponics ( needing to be applied 1-2x per week depending on plant ). That said it seems much more appropriate and deserving to be in it’s own wiki page.

In the interim, here are the top three Google search results on the subject

http://theaquaponicsource.com/2013/08/15/iron-in-aquaponics/

http://brightagrotech.com/iron-in-aquaponics/

Dr Wilson Lennard on Backyard Aquaponics and Adding Nutrients

Phosphates

Note, Phosphate’s play a crucial role in causing plant’s to seed/develop fruit, in “If however, you have vegetative crops (think basil, lettuce, kale, etc.) then excess phosphate (in part) can stimulate some of these crops to flower, which isn’t very desirable.”;

Cite SRAR 454, page 10, column 2, Paragraph 1

TODO – Need more citations and resources!

:—|:—
Dosage| Dependant on plant, Nate Storey recommends 10-20ppm to 20-40ppm dependant on plants.

Phosphorite

:—|:—
Common names| Multiple names/types
Common state| Ash/rock dust
Dosage| Dependent on plant

Cite Bright Agro tech – http://brightagrotech.com/phosphorus-in-aquaponics/#rock-phosphate

Bone Meal

Wiki article – http://en.wikipedia.org/wiki/Bone_meal

Wikipedia concern on toxcity

Research in the 1980s found that many bone meal preparations were contaminated with lead and other toxic metals, and is no longer recommended as a calcium source.
-http://en.wikipedia.org/wiki/Bone_meal#Background

Credits/contributions

— Zynix ( wiki article maintainer, spalling & gramer butcher ).
— Aquaponics-Heretic

Please PM /u/zynix for spelling, errors of fact, and anything else related to this page.

templates/housekeeping

Fact value
Common names
Chemical name
Common state
Dosage

Basic synopsis

Wikipedia Entry