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Is Water Onion a Good Plant for Peacock Cichlid (Aulonocara)?

Reviewed by Guidarium Editorial DeskUpdated April 28, 2026
Strong Fit

Water Onion is a strong fit for Peacock Cichlid (Aulonocara). The shared water window is realistic, and the plant has enough structure or resilience to be useful in a tank built around this fish. The match depends on anchoring and placement more than the water numbers alone.

Water Onion

Crinum thaianum

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PlacementBackground
LightModerate
DifficultyBeginner
Size150 × 30 cm

Peacock Cichlid (Aulonocara)

Aulonocara sp.

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TemperamentSemi-Aggressive
FamilyCichlids - African
Temp24–28°C
Water TypeFreshwater Only

Quick Decision

A plant can be technically compatible with a fish and still fail in the actual tank if the fish digs, chews, needs denser cover, or uses a different part of the layout.

Overall fit

84/100

The plant and fish suit each other well.

Water match

Workable overlap

Shared range: 24-28°C, pH 7.8-8, 10-15 dGH.

Plant pressure

Moderate

Water Onion needs thoughtful placement and anchoring.

Layout value

Moderate cover

Water Onion helps with provides surface cover, breaks lines of sight, and good grazing surface.

Plant and Fish Fit Notes

Use these signals to decide whether the plant is doing useful work for the fish, or whether it is only surviving beside it.

Temperature
Water Onion22-28°C
Peacock Cichlid (Aulonocara)24-28°C

Overlap: 24-28°C.

pH
Water Onion6-8
Peacock Cichlid (Aulonocara)7.8-8.6

Overlap: pH 7.8-8.

Hardness
Water Onion2-15 dGH
Peacock Cichlid (Aulonocara)10-25 dGH

Overlap: 10-15 dGH.

Water and flow
Water OnionFreshwater Only, Moderate (Standard)
Peacock Cichlid (Aulonocara)Freshwater Only, Moderate (Standard)

Flow expectations are close enough for one layout.

Space used
Water OnionBackground
Peacock Cichlid (Aulonocara)Bottom (Substrate) and Middle (Open Water)
Pressure signals
Water OnionHigh uproot resistance, Tough / leathery leaves
Peacock Cichlid (Aulonocara)Semi-Aggressive, Territorial (Defends specific area), Aggressive to same species/look-alikes, and Digger (Disturbs Substrate)

Plant pressure: Moderate.

Planting value
Water OnionProvides surface cover, Breaks lines of sight, and Good grazing surface, Nutrient-rich substrate preferred
Peacock Cichlid (Aulonocara)Sand (Sifters) and Smooth Gravel (Sensitive Barbels)

Shared Tank Conditions

Water Onion fits inside the water range normally used for Peacock Cichlid (Aulonocara). The shared window is about 24 to 28 °C, pH 7.8 to 8, and 10 to 15 dGH, which gives you enough room to aim for stable middle-ground conditions.

Both do best with moderate flow, so circulation does not need to be split into competing zones.

Both are suited to freshwater, so salinity does not add an extra planning problem.

Fish Pressure and Plant Resilience

Peacock Cichlid (Aulonocara) can still be rough on plants, but this pairing becomes more realistic when the plant is anchored well and used as part of a larger layout.

Water Onion has moderate cover density, high uproot resistance, and tough / leathery leaves. It can also help with surface cover, breaking up sight lines, and grazing surfaces.

The plant helps break up sight lines, which can soften territorial behaviour.

The point to watch is substrate activity from the fish means this planting style needs extra anchoring at first.

Layout Fit

Water Onion is a bulb / tuber plant usually used background.

Peacock Cichlid (Aulonocara) is an African cichlid, so the pairing works best when the planting style supports how that fish uses space and cover.

Water Onion reaches about 150 cm tall by 30 cm wide and is usually bulb / tuber on or partly in substrate with nutrient-rich substrate preferred. That makes placement and anchoring more important than simply adding a larger bunch of stems or leaves.

In this pairing, the useful plant values are surface cover, line-of-sight breaks, and grazing surfaces. Place it where Peacock Cichlid (Aulonocara) can actually use that structure instead of hiding the plant where it cannot do much.

Practical Recommendation

This is a sensible planted-tank choice for Peacock Cichlid (Aulonocara), especially when you want the plant to do real work as cover, sight-line structure, or habitat detail.

The decision should center on this signal: Substrate activity from the fish means this planting style needs extra anchoring at first.

Best Use Case

Water Onion is a strong choice for Peacock Cichlid (Aulonocara) when you want the plant to do real work in the tank, not just survive in the background. The pairing tends to perform best when the plant's cover, resilience, or placement naturally supports how the fish moves, hides, or claims space.

Frequently Asked Questions About Water Onion and Peacock Cichlid (Aulonocara)

Is Water Onion a good plant for Peacock Cichlid (Aulonocara)?

Water Onion is a strong fit for Peacock Cichlid (Aulonocara). The shared water window is realistic, and the plant has enough structure or resilience to be useful in a tank built around this fish. The match depends on anchoring and placement more than the water numbers alone.

Can Peacock Cichlid (Aulonocara) damage Water Onion?

Substrate activity from the fish means this planting style needs extra anchoring at first.

Do Water Onion and Peacock Cichlid (Aulonocara) share the same water conditions?

Water Onion and Peacock Cichlid (Aulonocara) share a workable water window around 24 to 28 °C, pH 7.8 to 8, and 10 to 15 dGH. Keep the tank near the middle of that overlap for the best long-term result.

What does Water Onion add to a tank with Peacock Cichlid (Aulonocara)?

The plant helps break up sight lines, which can soften territorial behaviour.

What is the main risk in this plant and fish pairing?

Substrate activity from the fish means this planting style needs extra anchoring at first.

Editorial Review

Guidarium Editorial Desk

Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.

Last reviewed
April 28, 2026
Last updated
April 28, 2026
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