Discus BreedingWater Quality, Tanks and Filtration
Discus breeding: pair tanks, grow-out tanks and one central filter, from spawn to sale in four months, water values, tank density and keeping disease out.
SYSTEM CONCEPTSee the mechanism.
Understand the duty.
Select a route or a stage to inspect the process. The cutaway explains the equipment and water environment; it is a teaching illustration, not a project drawing.
Manage the display
Record the stock, feeding and operating water volume.
Use the actual operating water volume, stock and feeding programme to establish the life-support review.
- Record the stock, feeding and operating water volume.
- Keep mechanical, biological and gas duties distinct.
- Review quarantine, maintenance access and safe water replacement.
Key takeaways
- Pair tanks run at 28 to 30 °C and pH 5.5 to 6.5.
- The cycle from spawn to sale takes about four months.
- Grow-out tanks need space and clean water. Density falls as fish grow.
- Central filtration with a drum filter and moving bed suits discus racks.

How discus breeding works
- Spawning, day 0Pair lays eggs on a surface.
- Hatching, after 2 to 2.5 daysWrigglers attach.
- Free-swimming, about 4 days after hatchingFry feed from parents.
- First food, day 7 to 10Brine shrimp nauplii.
- Separation, 3 to 5 weeksMove to grow-out tanks.
- Grow-out to 3 or 4 monthsReady to sell.


Water for pair tanks and grow-out tanks
| Value | Pair tanks | Grow-out tanks |
|---|---|---|
| Temperature | 28 to 30 °C | 29 to 30 °C |
| pH | 5.5 to 6.5 | About 6.0 to 7.0, steady |
| Conductivity | 35 to 80 µS/cm (RO) | Less critical |
| Ammonia and nitrite | 0 mg/L | 0 mg/L |
| Nitrate | Below 20 mg/L | Below 20 mg/L |
Work with your own numbers.
Use the tools below to explore the relevant arithmetic. Enter measured values or declared assumptions. An estimate does not establish equipment capacity, biological performance or a safe operating limit.
Water-change volume planner
Calculate the volume changed per event and the original-water fraction remaining after repeated equal changes.
Assumptions and limits
Assumes complete mixing between equal changes. Match replacement-water chemistry and temperature; this is not a safe-change prescription or a treatment guarantee.
Flow & turnover planner
Relate a measured water volume to a selected turnover time. Confirm the time from the application and hydraulic design.
Assumptions and limits
A planning allowance is your assumption. This calculation does not choose a filter, prove treatment capacity or account for pump head.
Convert units before you calculate
Planning arithmetic · inputs remain visible for review · example values are not operating recommendations
Grow-out tanks: where the space goes
| Age | Water per fish | Fish per tank (example) |
|---|---|---|
| Up to 2 weeks | 2.5 L | About 90 young |
| Up to 6 weeks | 5 L | About 45 young |
| 12 weeks, best growth | 7.5 L | About 30 young |
Why a drum filter and moving bed suit a discus rack
Discus eat rich food and need very clean water. A drum filter takes out waste before it rots and a moving bed biofilter handles ammonia, in one central system. See rack filtration.
Building a rack and keeping disease out
Use clean intake water, UV-C, strict hygiene and quarantine. See quarantine.
Plan around the collection
Use these questions to prepare a project brief or an operating review. Check an item only when the information has been recorded for your installation.
This checklist is a working aid in the current page session, not a saved maintenance record.
Discus Breeding FAQ
How long from spawn to sale?
About four months.
What pH do discus need?
5.5 to 6.5 in pair tanks.
Do I need RO water?
For breeding, usually yes.
More guides related to discus breeding
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