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STATUS: INCOMPATIBLE ⬌ MATRIX CORRELATION INDEX

Can you keep Discus and Harlequin Rasbora together?

Algorithmically generated environmental and behavioral compatibility report.

DiscusSymphysodon aequifasciatus
mid Layerpeaceful
incompatible
Harlequin RasboraTrigonostigma heteromorpha
mid Layerpeaceful
INCOMPATIBLE

Algorithmic Assessment

Water temperature envelopes clash. Harlequin Rasbora requires 73-80°F, while Discus requires 82-88°F. Coldwater/coolwater and tropical species cannot share the same environment.

Scientific Parameter Comparison

Cross-reference water chemistry, temperature range envelopes, and physical dimensions of Discus and Harlequin Rasbora.

Parameter MetricDiscusHarlequin RasboraCalculated Overlap
Temperature Range82°F – 88°F73°F – 80°FNo Overlap (Mismatch: 2°F)
pH Chemistry5.0 – 6.56.0 – 6.86.0 – 6.5
Min. Tank Capacity50 Gallons10 Gallons50 Gallons (Minimum)
Aquatic Strata ZonemidmidShared Zone (Layer Conflict)
Adult Size (Max)8.0" (20 cm)1.8" (4 cm)Ratio: 1 : 4.6

⚠ Physiological Mismatch Report

Our stocking engine calculations indicate that putting these two species in the same tank causes acute physiological strain. Below are the calculated parameters that violate safe cohabitation ranges:

Temperature Deficit2.0°F gap

Discus requires 82-88°F, while Harlequin Rasbora needs 73-80°F.

Predation Threat MetricsSize Ratio: 4.6 : 1

Larger predators typically consume tankmates that fit into their mouths. Keeping a 8" species with a 1.75" species is dangerous.

⚔️ Do Discus and Harlequin Rasbora Fight?

Environmental or structural requirements between these species clash too heavily to allow cohabitation. Water temperature envelopes clash. Harlequin Rasbora requires 73-80°F, while Discus requires 82-88°F. Coldwater/coolwater and tropical species cannot share the same environment.

🍽️ Swimming Layers & Feeding Competition

To satisfy their dietary requirements, offer a varied feeding schedule. Sinking pellets or wafers are ideal for bottom dwellers, while floating flakes or micro-granules support mid and top dwellers. Both species reside in the mid layer. Feeding them simultaneously in different corners of the tank is highly recommended to distribute food and prevent any resource competition in their shared vertical zone.

📏 Size Difference & Predation Threat

A major physical size discrepancy exists between these two species. The Discus grows to 8.0 inches, which is over 5 times larger than the Harlequin Rasbora at only 1.8 inches. There is a high risk of predation, as predatory fish will naturally consume any tank mate that can fit into their mouths.

Safe Tankmate Alternatives for Discus

Since the pairing between Discus and Harlequin Rasbora is flagged as incompatible, here are 3 peaceful community tankmates that share a flawless compatibility profile with Discus and match similar water parameters:

Discusmid Layer
Scientific NameSymphysodon aequifasciatus
Min Tank Capacity50G
Aggressionpeaceful
Temp Envelope82°F - 88°F
pH Chemistry5.0 - 6.5
Scientific NameTrigonostigma heteromorpha
Min Tank Capacity10G
Aggressionpeaceful
Temp Envelope73°F - 80°F
pH Chemistry6.0 - 6.8

Chemistry & Habitat Analysis

Temp Envelope
No Overlap
Envelopes mismatch.
pH Chemistry
6.0 - 6.5
Shared safe pH bounds.
Combined Min Tank
50 Gallons
Lowest acceptable volume.

Frequently Asked Questions: Discus & Harlequin Rasbora Compatibility

Are Discus and Harlequin Rasbora good tank mates?

Water temperature envelopes clash. Harlequin Rasbora requires 73-80°F, while Discus requires 82-88°F. Coldwater/coolwater and tropical species cannot share the same environment.

Can you put Discus and Harlequin Rasbora in the same tank together?

Environmental or structural requirements between these species clash too heavily to allow cohabitation. Water temperature envelopes clash. Harlequin Rasbora requires 73-80°F, while Discus requires 82-88°F. Coldwater/coolwater and tropical species cannot share the same environment.

What water temperature and pH parameters do Discus and Harlequin Rasbora need?

Both species require compatible parameters. Discus needs a temperature of 82°F to 88°F and a pH of 5.0 to 6.5. Meanwhile, Harlequin Rasbora needs a temperature of 73°F to 80°F and a pH of 6.0 to 6.8. Shared overlap range: No safe temperature overlap temperature and 6.0–6.5 pH overlap.

What is the minimum combined tank volume required to house Discus and Harlequin Rasbora?

To successfully house both species together, the minimum baseline capacity is 50 gallons. Because both Discus and Harlequin Rasbora are peaceful community species, no extra territorial buffer volume is required.