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STATUS: INCOMPATIBLE ⬌ MATRIX CORRELATION INDEX

Can you keep Discus and Molly together?

Algorithmically generated environmental and behavioral compatibility report.

DiscusSymphysodon aequifasciatus
mid Layerpeaceful
incompatible
MollyPoecilia sphenops
top Layerpeaceful
INCOMPATIBLE

Algorithmic Assessment

Water acidity (pH) parameters clash. Molly prefers a pH of 7.5-8.5, while Discus requires a pH of 5-6.5. There is no overlapping safe pH range.

Scientific Parameter Comparison

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

Parameter MetricDiscusMollyCalculated Overlap
Temperature Range82°F – 88°F72°F – 78°FNo Overlap (Mismatch: 4°F)
pH Chemistry5.0 – 6.57.5 – 8.5No Overlap (Mismatch: 1.0)
Min. Tank Capacity50 Gallons20 Gallons50 Gallons (Minimum)
Aquatic Strata ZonemidtopSeparated Layers
Adult Size (Max)8.0" (20 cm)4.0" (10 cm)Ratio: 1 : 2.0

⚠ 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 Deficit4.0°F gap

Discus requires 82-88°F, while Molly needs 72-78°F.

Acidity/pH Gap1.0 pH difference

Discus thrives in pH 5-6.5, while Molly needs pH 7.5-8.5.

⚔️ Do Discus and Molly Fight?

Environmental or structural requirements between these species clash too heavily to allow cohabitation. Water acidity (pH) parameters clash. Molly prefers a pH of 7.5-8.5, while Discus requires a pH of 5-6.5. There is no overlapping safe pH range.

🍽️ 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. The Discus occupies the mid layer, while the Molly occupies the top layer. This separation of swimming zones naturally minimizes direct interactions and reduces competition during feeding times.

📏 Size Difference & Predation Threat

Both species are closely matched in physical dimensions, with Discus growing to 8.0 inches and Molly reaching 4.0 inches. This size balance ensures neither species holds a physical dominance advantage.

Safe Tankmate Alternatives for Discus

Since the pairing between Discus and Molly 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
Mollytop Layer
Scientific NamePoecilia sphenops
Min Tank Capacity20G
Aggressionpeaceful
Temp Envelope72°F - 78°F
pH Chemistry7.5 - 8.5

Chemistry & Habitat Analysis

Temp Envelope
No Overlap
Envelopes mismatch.
pH Chemistry
No Overlap
Acidity requirements clash.
Combined Min Tank
50 Gallons
Lowest acceptable volume.

Frequently Asked Questions: Discus & Molly Compatibility

Are Discus and Molly good tank mates?

Water acidity (pH) parameters clash. Molly prefers a pH of 7.5-8.5, while Discus requires a pH of 5-6.5. There is no overlapping safe pH range.

Can you put Discus and Molly in the same tank together?

Environmental or structural requirements between these species clash too heavily to allow cohabitation. Water acidity (pH) parameters clash. Molly prefers a pH of 7.5-8.5, while Discus requires a pH of 5-6.5. There is no overlapping safe pH range.

What water temperature and pH parameters do Discus and Molly 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, Molly needs a temperature of 72°F to 78°F and a pH of 7.5 to 8.5. Shared overlap range: No safe temperature overlap temperature and No safe pH overlap overlap.

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

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