Fish Lab & Aquaria – Marine Life in the Maldives

Large Aquarium

There have been no changes in our main display aquarium during February, and all species and corals continue to do well.

Plankton Production

Rotifers – at the start of February, there was a crash in rotifer numbers, but we have since recovered the populations.

Artemia – we are continuing to feed our Artemia with diatoms (Thalassiosira weissflogii), reducing the need for algae, so we have scaled down algae production from two 100L buckets to a single 20L bucket.

Jellyfish – Aurelia aurita

We are maintaining a population of 296 jellyfish in the Kreisel tank under our current protocols (water changes maintained at 35% every two days, with a larger water change when required).
On 15 February, we started a new strobilation; the ephyra development stage are expected by 8 March. The large display cylinder was drained and thoroughly cleaned in preparation for restocking.

from: Jellyfishes – Diversity, Biology

Ornamental Fish Breeding

• Common clownfish [Australia] (Amphiprion ocellaris) – the juveniles continue to thrive and are beginning to show hosting behaviour on the artificial anemone we made from rubber bands. A real anemone has now been added to the tank (relocated from the display aquarium); it has acclimatised well but the juveniles are not yet interested.
  The breeding pair in Tank 11 continue to produce eggs at a slower rate since being taken off the breeding pair diet.
• Clark’s clownfish (Amphiprion clarkii) – several clutches of eggs were laid during February, but were lost due to poor timing and Fish Lab logistics.
• Maldivian clownfish (Amphiprion nigripes) – one mortality this month (Tank #23), so we introduced the single male from Tank #25. After careful monitoring for signs of aggression, we were pleased to see they have now formed a new breeding pair.
  The pair in our main display aquarium continues to produce eggs, and one clutch was successfully collected this month.
• Peacock damsel (Pomacentrus pavo) – the diatoms proved to be a successful initial food source for the larvae, increasing survival times.
• Seahorses (Hippocampus kuda) – our male seahorse now has a defined brood pouch, although we did lose one of the females (Tank #32).
• Humbug damselfish (Dascyllus aruanus)– continue to show signs of mating behaviour, and so we have introduced a PVC breed pipe to their tank.
• Sexy shrimp (Thor amboinensis) – eggs were observed on the body of the shrimp, which should develop over the next 14 to 20 days.
• Coral banded shrimp (Stenopus hispidus) [female] – now recovered from her moult, so will hopefully resume mating behaviours in the coming weeks.

Small Marine Aquaria

During February, our small marine aquaria experienced unusual issues with water flow, due to the turtle tanks being empty. Water levels regularly dropped, and deep cleaning was required more frequently due to increased algal growth.
Three fish species continue to lay clutches of eggs, that are rapidly eaten by other resident fish or crabs.

Aquarium One

• Mini coral frame – some paling of the coral fragments, likely due to the irregular water flow issues.
• Maldivian clownfish (Amphiprion nigripes) – laid on two different locations this month.
• Sea star (Linckia multifora) – developed an infection in one leg (which has since shortened in length).

Aquarium Two

• Mini coral frame – some paling of the coral fragments, likely due to the irregular water flow issues.
• Clark’s clownfish (Amphiprion clarkii) – laid on their preferred spot, on a rock covered with CCA. They continue to lay mostly during the afternoon (around 14:30 resort time).
• Blue damselfish (Chromis viridis) – laid on the wall of the aquarium again.
• Mushroom corals – continually being moved around by the crabs.