What is the
WQ Map?

manage RAS water chemistry...

...as simply as using Google MapsTM

  • Anyone who uses Google MapsTM will be able to control water chemistry with the WQ Map quickly & accurately after less than 30 minutes of training.
  • The WQ Map boosts daily productivity , guides remediation of exceptional water-quality problems, & greatly reduces staff training time.
  • The WQ Map lowers a tech barrier that limits RAS adoption: It makes precision water-quality management accessible to aquaculture entrepreneurs who have valuable husbandry & mechanical skills but neither a deep background in chemistry nor deep pockets to fully automate a production facility.

For a thorough introduction, request a demo and/or see: Appendix V in Tzachi Samocha's biofloc book.

The Water-Quality Map (WQ Map)

empty wq map

The Water-Quality Map (WQ Map)

The WQ Map is an innovative tool for quick & precise management of water chemistry in recirc aquaculture systems.

Anyone who plans their travel with Google MapsTM already has the skills to control aquaculture water quality with the WQ Map -- no background in natural water chemistry required.

The map sits in the center of the top row. Input controls modify its appearance & output panels display results.

The main input panel slides out by tapping the green vertical strip along the left border.

Entering WQ data

Enter WQ data

Entering WQ data

The sidedrawer has six accordion controls that individually toggle to expose inputs for data that all facilities collect to describe water-quality state.

At a minimum, these include water volume, temperature, salinity, pH, alkalinity, & Total Ammonia-Nitrogen (TA-N).

Managing water-reuse systems expands the list to, at least, nitrate, nitrite, calcium, magnesium, sodium, & potassium.

The controls illustrated here define the Green Zone -- the region of a species' optimal growth & survival.

Like a topographic map of pH

empty wq map

Like a topographic map of pH

pH is a "master variable", but pH control alone is not enough to maintain a healthy culture environment.

Both pH & alkalinity must be managed for precise control of aquaculture water chemistry.

This is at the core of the WQ Map: alkalinity is on the y -axis and lines of equal pH are projected onto the map surface.

The pH lines are like lines of equal elevation on a topographic map: Where they're closer together, pH can change faster -- and that means weaker buffering.

Plot your position on the map

Fifth image

Plot your position on the map

Entering pH & alkalinity marks your culture water's position (for the system's temperature & salinity) on the WQ Map.

In this example, the blue pin represents typical seawater values...

  • ...pH 8.1
  • ...alkalinity 2.3 meq/kg (~115 ppm)

...at 25° C (77° F) & 34.5‰.

In terms of the Google MapsTM analogy, this is the starting point for your water-quality adjustments.

Steer Clear of Danger

First image

Steer Clear of Danger

The WQ Map enhances water-quality management by clearly displaying regions of sub-optimal culture conditions.

Defining your species' critical requirements for...

  • ...un-ionized ammonia-nitrogen (UIA-N)
  • ...carbon dioxide (CO2)

...and entering TA-N concentration overlays Danger Zones of:

  • high UIA-N (red area, upper left)
  • high CO2 (red area, lower right)

The Green Zone

First image

The Green Zone

Instead of plotting the Danger Zones, it generally is more informative to display the Green Zone.

That's the region where the water chemistry of the culture environment satisfies your species' growth & survival requirements.

Add the draggable target marker to the map and your "water quality game" becomes making chemical adjustments that keep the target within the Green Zone.

A Common Adjustment Mistake

bicarb additions

A Common Adjustment Mistake

When plotting a course for the Green Zone, many aquaculturists reach for sodium bicarbonate (baking soda, NaHCO3), but this almost never is sufficient by itself.

As illustrated for this case, adding only sodium bicarbonate follows the orange vector from the initial WQ () toward the upper right -- and this misses the Green Zone altogether.

It also is the source some confusion: NaHCO3 doesn't change pH much within the pH range of most aquaculture. Here, 4.3 kg (9.5 lb) increases pH only one-tenth of a unit: 6.8 to 6.9.

Getting Adjustment Directions

First image

Getting Adjustment Directions

The WQ Map solves this problem: Chemical adjustment options that change water quality from the initial to the target point are displayed whenever the target marker is set.

In this example, one of 15 options is...

  • ...3.31 kg of sodium carbonate (Na2CO3)
  • ...108.3 g of calcium hydroxide (Ca(OH)2)

Note that other reagents in the list -- CaCl2, MgCl2, & KCl -- keep the major ionic ratios in balance.

(Managing ionic ratios is addressed in a separate tutorial.)

Manage carbonate saturation (Ω)

Third image

Manage carbonate saturation (Ω)

The saturation states of aragonite & calcite -- crystaline forms of calcium carbonate -- partly determine...

  • ...the carapace integrity of shrimp
  • ...healthy bones in fish
  • ...the strength of sea urchin tests

...as well as other water-chemistry concerns.

Despite its importance, many aquaculturists do not account for Ω (omega) in their WQ management program.

The WQ Map resolves this issue by integrating Ω into its routine water-chemistry analysis.

Decrease production uncertainty

Decrease production uncertainty

Decrease production uncertainty

The WQ Map uses data you already collect to forecast future water quality resulting from...

  • ...feeding
  • ...evaporation
  • ...adding make-up water
  • ...algal metabolism in IMTA systems
  • ...organic carbon additions in biofloc systems

This helps producers anticipate problems before they occur, especially in high-density, warm-water RAS.

For a thorough introduction, request a demo and/or see: Appendix V in Tzachi Samocha's biofloc book.