Troubleshooting
Phytoplankton Crash, BGA, and Overbloom
01 — Overview
What this protocol is for
A 5-day corrective schedule for three related in-crop problems: phytoplankton crash, blue-green algae (BGA) presence, and overbloom conditions. Uses FytoShade, SoilGro, molasses, NitroGro, and optionally AmmoTrap if total ammonia nitrogen (TAN) exceeds 3 ppm.
Primary Objective
Restore water quality and phytoplankton balance after a crash, BGA event, or overbloom using a structured 5-day product schedule.
02 — Indications
When to use this protocol
All pond types, both species, during grow-out when phytoplankton crash, BGA, or overbloom occurs
Important Notes
- !
Keep aerators running throughout. Phytoplankton crash increases organic matter in the water column and creates high BOD and low DO risk.
- !
If water colour is dark with high organic matter, remove 10 cm of bottom water via central drain before Day 1 treatment.
- !
Water colour and the presence of foam are indicators of high organic load.
03 — Procedure
Step-by-step instructions
- 1
Day 1: FytoShade application
Apply FytoShade to address BGA or overbloom. If water colour is dark or organic load is high, remove 10 cm of bottom water via central drain before applying treatment.
- 2
Days 2 to 4: SoilGro for 3 consecutive days
Apply SoilGro for 3 consecutive days to break down organic matter.
- 3
Days 3 to 5: Molasses for 3 consecutive days
Apply molasses 2 kg per hectare for 3 consecutive days to balance C/N ratio.
- 4
Days 3 and 5: NitroGro
Apply NitroGro on Days 3 and 5 to enhance nitrification.
- 5
If TAN exceeds 3 ppm: AmmoTrap
If total ammonia nitrogen exceeds 3 ppm after the crash: apply AmmoTrap at 0.3 ppm.
04 — Parameters
Key parameters to monitor
Parameter
Target / Range
Molasses: Days 3 to 5
2 kg per hectare per day
AmmoTrap dose
0.3 ppm
AmmoTrap trigger
TAN above 3 ppm after crash
05 — Products
Products used in this protocol
Each product name links to its Blue Aqua product page for specifications and purchasing.