They will grow without CO2, but it won't be as much. Hydrocotyle Tripartita is not picky when it comes to water parameters, but optimal growth can be observed at 72-82°F (22-28°C) and pH level of 6.0 to 7.7. If the conditions are optimal, Hydrocotyle Tripartita will grow to a height of 2-4 inches (5-10 cm).