Rotala Blood Vomit Care Propagation: Rare Red Stem
The unsettling name hides one of the more striking red stem plants to enter the hobby in the last few years. This Rotala blood vomit care propagation guide covers what the plant actually wants, which is not quite what the forums insist, along with the trimming rhythm that keeps a dense bush rather than a stretched-out skeleton. The notes draw on two years of tank trials at Gensou Aquascaping in 5 Everton Park, where the plant has survived the usual SG temperature challenges without major incident. If you are paying 8 to 12 dollars a stem, understanding the husbandry before purchase is worth the read.
Species Identity and Naming
“Blood vomit” is an informal trade name rather than a scientific one, and the plant most commonly sold under this label is a colour-selected line of Rotala close to macrandra. Some vendors ship genuine ma macrandra variants under the name, others ship a selected rotundifolia form, and the two have different light requirements. Check leaf shape on arrival: broad, rounded leaves indicate macrandra lineage, narrower lanceolate leaves indicate rotundifolia lineage. Care recommendations below assume the macrandra form.
Lighting for Deep Red Colour
This plant demands high light. Target 80 to 120 PAR at substrate level, which typically means a Twinstar 600EA or Chihiros WRGB II at near-maximum output with the fixture hung 20 cm above the water. Red spectrum emphasis from the fixture helps visually but does not replace absolute intensity. Shorter photoperiods of 6 to 7 hours at high intensity produce better colour than longer softer schedules; the plant shuts down chlorophyll production quickly under bright light, shifting to carotenoids.
CO2 and Flow Requirements
CO2 at 30 to 35 ppm is non-negotiable for stable red colour. Below 25 ppm the plant deteriorates within a fortnight, going pink then green then stalling. Flow pattern matters as much as absolute concentration; dead zones behind hardscape where CO2 does not reach the leaves produce uneven colouration. A mature aquarium CO2 diffuser ceramic and a spray bar positioned for lateral water movement across the stem group give the best results.
Lean Dosing Versus EI
This is where forum advice splits. Estimative Index schedules push nitrate to 15 to 20 ppm, which produces rapid growth but dulls red tones toward pink. Lean dosing at 5 to 8 ppm nitrate, 1 to 2 ppm phosphate and elevated iron at 0.5 ppm produces slower growth with much deeper red. In Singapore tanks running on soft tap water the lean approach is easier to maintain; the lean dosing method planted tank piece has the full recipe.
Temperature Tolerance and Fans
The plant tolerates 22 to 28°C but colour intensifies noticeably below 26°C. In un-chilled SG tanks sitting at 28 to 29°C, the leaves run pink rather than the deep crimson seen in northern tanks kept cooler. A $15 clip fan across the surface drops tank temperature 2 to 3°C through evaporation and transforms colour response within a week. For serious display tanks a chiller at 24°C is the upgrade worth considering.
Substrate and Root Feeding
A rich aquasoil substrate like ADA Amazonia, Landen or UNS Controsoil carries the plant through the first six months. After that, root tabs placed directly under stem bases every two months keep the growth rate steady. Inert gravel or sand will stunt blood vomit within a month regardless of water column dosing, because the species is a split feeder that takes most of its nitrogen from substrate.
Trimming for Density
Top-cut only, never hack from the middle of the stem group. Snip the tops at the desired height, replant the cut tops elsewhere, and leave the old stems in place; they will sprout two to four lateral branches within ten days. This technique builds a dense bush over three to four trim cycles rather than immediately. Avoid the common mistake of pulling old stems when they look bare, as these are the ones that generate next month’s bush. See the how to trim aquarium plants guide for cut technique.
Propagation Pathways
Stem tops are the fastest propagation route: trim 8 to 10 cm off growing tips, strip two leaf pairs from the base and replant directly into substrate. Side shoots from older stems can also be separated once they reach 5 cm. Commercial growers use emersed culture trays to produce bulk stock, which works in home setups with a humid cover if you want to run a growing-out side project. Pricing in Singapore sits at 8 to 12 dollars per 15 cm stem, dropping to 4 to 6 dollars if you buy from private propagators through Carousell.
Common Problems
Melting new tips usually means CO2 has dropped below 25 ppm or flow is stagnant in that area. Leaf curling indicates calcium deficiency, uncommon in tap water-fed tanks but seen in RO setups without proper remineralisation. Black spots on older leaves point to phosphate deficiency. Pale green stems mean light is insufficient, not nutrition. Rule out light and CO2 first, before assuming a nutrient problem.
Pairing in a Scape
Blood vomit works as a central colour accent rather than a background filler. Plant in groups of 8 to 12 stems in a tight cluster to amplify visual impact. Surround with mid-green plants like Staurogyne repens or Hygrophila pinnatifida to let the red saturate the eye. Pair with finer-leaved reds like Rotala wallichii for texture variation. The aquascape with Rotala varieties only piece shows genus-exclusive layout ideas.
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