AQUATIC PLANTS & LIVESTOCK

Monte Carlo

Fast-spreading carpeting plant that needs high light, CO₂ and patience.

Planting stage Plants

Unplug before servicingHands out of the water firstDrip loop on every cableTest before you dose30 ppm CO₂ ceilingCycle before stocking

Plants

Specification
Type	Stem, carpeting
Light demand	High
CO₂ demand	High
Growth rate	Fast when conditions met
Carpet height	2–4 cm
Planting density	Very dense — 1–2 cm spacing

Technical parameters
pH range	6.0–7.5
Temperature	20–28 °C
Time to full carpet	6–10 weeks
Nitrate target	10–20 ppm
Trimming	Top off every 2–3 weeks
Dry start	4–6 weeks before flooding

Monte Carlo is a small-leaved stem plant that, under strong light, grows horizontally rather than upward and forms a dense green carpet across the substrate. It is the modern default for a planted carpet, having largely displaced the more demanding Hemianthus callitrichoides.

Its requirements are unambiguous: high light, consistent CO₂ at around 30 ppm, and nutrients in proportion. Given all three it will spread across a 60 cm tank in six to ten weeks. Given any two of the three, it stretches upward into a leggy mess and the substrate shows through.

The classic failure is a dry start — planting the carpet before flooding the tank and letting it establish in humid air, where CO₂ is unlimited. A dry start is slower and messier, but it gets roots established without an algae phase and is much more reliable than planting into a flooded tank with immature filtration.

Safety and welfare

A dense carpet traps debris. Vacuum the surface gently during water changes or organic matter accumulates underneath and the carpet lifts.
If the carpet starts to lift at the edges, it has run out of light at the base. Trim it back and increase flow across the substrate.
Plant into a shallow bed, not a deep one. Monte Carlo roots shallowly and deep substrate goes anaerobic beneath it.

Using it well

Separate the pot into small clumps of three or four stems and plant them 1–2 cm apart. A carpet planted in clumps fills in weeks; one planted as whole pots takes months.

Trim the carpet with curved scissors in a shallow arc. A flat cut leaves the top scorched and brown for a week.

If it is growing upward instead of sideways, light is the limiting factor. Raise intensity before increasing CO₂.

Pairs with

Aqua soilDragon stoneSeiryu stoneCO₂ regulatorCherry shrimp

Worth knowingCherry shrimp graze a Monte Carlo carpet constantly and will not damage it.

Note. Parameters are conventional ranges across the category, not the claim of any one manufacturer. Nothing on this page is for sale and no outcome for any plant or animal is guaranteed. Simulator output elsewhere on this site is a simplified model, not a measurement — confirm everything with a test kit and the equipment's own instructions.

Monte Carlo

Using it well

Pairs with

Works alongside