Frogspawn coral is a stunning large polyp stony coral species that’s incredibly popular with reef aquarium hobbyists. This coral looks gorgeous and is pretty straightforward to care for, making it a great choice for beginners and experienced marine tank keepers alike.
Read this guide to learn more about this beautiful coral, discover how to care for it, and ensure it thrives in your tank!
Frogspawn Coral – At a Glance
|Frogspawn Coral Info|
|Scientific Name||Euphyllia divisa|
|Common Name||Frogspawn coral, grape coral, wall coral, honey coral, or octopus coral|
|Origins||Indo-Pacific Ocean, specifically Southeast Asia, Australia, Fiji, Solomon Islands, Ryukyu Islands, Great Barrier Reef|
|Colors||Fluorescent green and yellow, white, or pink|
|Temperament||Aggressive toward nearby corals|
|Lighting||Can live under regular lighting but displays more vibrant colors under brighter lights|
|Tank Placement||Middle to top of the aquarium, 6 to 8 inches away from other corals|
|Flow Rate||Low to moderate flow|
|Temperature Range||72° to 78°F|
|pH Range||8.1 to 8.4|
|Salinity||1.022 to 1.025|
|Hardness||8 to 12 dKH|
|Propagation||Relatively easy to propagate by fragging|
Origins and Natural Habitat
Frogspawn coral grows naturally in the Indo-Pacific Ocean, on the Great Barrier Reef, Fiji, the Solomon Islands, the Ryukyu Islands, and Tonga. The coral forms colonies of average size, preferring rocky slopes to sandy substrates and growing at depths of 120 to 140 feet. However, you do sometimes find these beautiful corals growing happily in bright sunlight.
Frogspawn coral is also sometimes called Grape coral, Wall coral, Honey coral, and Octopus coral. However, in this guide, we refer to it by its most common name, Frogspawn coral. One big plus point of this coral is that the polyps stay out 24/7, making it perfect for viewing in a home marine tank.
The main Downside of this coral is that it’s known for being aggressive and bullying other corals for space, so correct placement is critical for harmony in your reef setup.
Types of Frogspawn Coral
There are two species of Frogspawn coral; wall (Euphyllia divisa) and branching (Euphyllia paradivisa). In addition, hobbyists have hybridized the species to create unique formations and colors between the two varieties.
Branching Frogspawn Coral (Euphyllia paradivisa)
Branching Frogspawn is the most common variety in the hobby, and you can identify them by looking at the coral’s base, where you’ll see that each polyp emerges from its own skeleton. This species is fast growing, maturing in just a few months, and spreading throughout an aquarium.
Wall Frogspawn Polyps (Euphyllia divisa)
Wall Frogspawn polyps have a common calcium carbonate base, grow more slowly, and don’t expand as wildly as Branching Frogspawn. Instead, this coral spreads in one direction and is more challenging to care for, which is why they’re not so popular or common in the hobby.
Frogspawn Coral Appearance
Frogspawn coral is named for the shapes formed by the polyps clusters that resemble a frogspawn mass. However, what makes this coral so popular are the bright, fluorescent colors of the coral’s tentacle tips, which are especially vibrant under subdued lighting. You can expect to find green, yellow, variations of pink, and white, and there are even varieties in blue and orange, although those are harder to come by.
This species of coral generally grows up to 10 inches wide, creating a fabulous, almost neon display in the reef tank. As mentioned above, Frogspawn coral can grow upward to create a wall effect or branch out in all directions.
Are Frogspawn Corals Beginner-Friendly?
Although you do need some knowledge to care for Frogspawn coral, you don’t need to be an expert to keep it in your aquarium. Provided you understand the core water parameters the species needs to thrive, and you appreciate its aggressive nature, it’s relatively straightforward to create a suitable environment where it will thrive.
It’s extremely important to get the placement of this coral species correct. This coral is better placed closer to the top of your tank than the middle, especially if you have low to moderate lighting. That ensures the coral gets the light it needs for growth and good overall health.
In addition, Frogspawn coral has nematocysts (stinging cells) at the end of each of its tentacles that can inflict serious damage on other corals. Ideally, you should place the coral in the middle or upper area of your tank and allow at least a 6 to 8-inch buffer between it and any other coral species you have.
The reason for that is that these corals are quite aggressive, using their sweeper tentacles to clear space for themselves by attacking surrounding corals. Unfortunately, the feisty Frogspawn usually wins the battle for aquarium real estate, stressing and even killing off weaker coral species. The exception to that rule is other Euphyllia species like Hammer or Anchor corals, which belong to the same genus, making them immune to the Frogspawn’s stinging tentacles.
In their wild environment, Frogspawn corals choose rocky sites because they will collapse on a sandy substrate. For that reason, you need to replicate that in the aquarium. Collapse can injure the coral’s tentacles, exposing the organism to severe health problems. For the best growth, we recommend placing your coral frag at an angle so that it can grow both vertically and branch out.
Frogspawn Coral Care Guide
In this part of our guide, we explain how to care for Frogspawn coral.
The ideal tank size for Frogspawn coral is at least 50 gallons. This coral has quite a fast growth rate and does need space just spread out, bearing in mind its aggressive tendencies.
If you want to give your coral the best chance of growing well and staying healthy, you must get the water parameters absolutely correct. Although Frogspawn coral can tolerate a reasonable range of parameters, you should try to keep things as close to the ideal as possible, as follows:
- Water temperature: 72° to 78°F
- pH levels: 8.1 to 8.4
- Water hardness: 8 to 12 dKH
- Specific gravity: 1.022 to 1.025
We recommend regularly using a high-quality water testing kit to be sure that the levels in your tank stay within the recommended parameters. That means you can spot any fluctuations quickly and make any adjustments before they become a serious issue.
Frogspawn corals benefit from the addition of supplementary nutrients, especially magnesium and calcium. If your coral doesn’t get enough calcium, it won’t grow, so levels must be around 350 to 450 ppm. In addition, magnesium balances calcium, and that level needs to be between 1,200 and 1,350 ppm. Trace elements, such as strontium, should also be considered; levels of around 8 to 10 ppm are ideal.
Routine water changes will help maintain ideal levels without too much trouble, but always test your water afterward and make any necessary adjustments.
Frogspawn coral needs a moderate flow rate, but don’t go overboard, or you risk negatively impacting polyp health and growth. The other benefit of a decent current through the tank is that the flow makes the coral polyps sway and really highlights their glorious colors.
This coral doesn’t appreciate very bright light and does fine under regular marine lights. Note that sudden light fluctuations can damage the coral or trigger an adverse reaction that sometimes can’t be reversed, so do take your aquarium lighting seriously.
Moderate lighting of 50 to 150 PAR is fine for Frogspawn corals but don’t use metal halides for Frogspawn corals as they generate too much heat.
Too much heat causes the corals to bleach or expel the symbiotic zooxanthellae in their cells, and that kind of stress damage usually can’t be repaired.
What To Feed Your Frogspawn Corals
LPS corals, like Frogspawn corals, contain symbiotic zooxanthellae, which photosynthesize and provide the coral with sugar in the form of glucose in return for a home.
However, the coral needs to supplement the nutrients provided by the zooxanthellae, and it does so by extending its polyps to catch and eat tiny zooplankton floating in the current. So you’ll need to provide your Frogspawn coral with additional food by spot-feeding or target-feeding them once a week.
Like little kids, Frogspawn corals can be quite fussy about their food, and they will spit out offerings they don’t like! That said, sometimes, you might just need to cut the food into smaller portions to make it easier for the coral to eat.
You can offer your corals commercially prepared pellet foods that work quite well and feed them whole foods, provided you cut them up into tiny pieces. Note that if the food is too large, the polyp will see it as a threat and retract. Frozen foods are good, but do thaw them before you feed them to your Frogspawn corals.
Foods that these corals love include:
- Brine shrimp (enriched)
- Mysis shrimp
All these foods are readily available from most fish stores, and you’ll find them in the freezer cabinet.
Frogspawn corals display 24/7, making them a fantastic addition to any marine display tank, and provided you keep reef-safe livestock species; the corals should thrive and set up healthy colonies.
Frogspawn coral polyps can also provide protection for some inverts and fish by using their sweeper tentacles to push away more aggressive corals. The following species can make good tank mates for Frogspawn corals.
However, do take care when choosing tank mates for your Frogspawns since those brightly colored round polyps will tempt many invertebrates and fish to nibble on them or try to make a home within the coral’s waving tentacles.
For that reason, we strongly recommend you avoid the following fish and invert species:
- Emerald crabs
- Hermit crabs
Finally, despite the fact that they also belong to the Euphillia species, be careful if you keep Torch corals, keeping them well out of reach of the Frogspawns. Torch corals are more aggressive than Frogspawns and will outcompete them for space.
How Do Frogspawn Corals Reproduce?
Frogspawn corals contain both male and female gametes but can also reproduce asexually to build new colonies.
In the tank scenario, sexual reproduction doesn’t work so well. In the wild, the corals release male and female gametes simultaneously. The fertilized eggs then hatch into free-swimming planula larvae, settling on the substrate to form a polyp. In an aquarium, the eggs and larvae usually get eaten by fish and inverts before they have a chance to mature into polyps.
However, captive Frogspawn corals can bud, detaching groups of polyps, complete with skeleton bases, or detaching a tentacle. Both options then fix themselves to a firm anchor point on the substrate and create a new colony.
You can create new colonies of Frogspawn corals by fragging, although that’s easier with branching than wall varieties. Here’s how to do it!
What You’ll Need:
- Start by taking a healthy coral with a solid color, lots of polyps, and no damage.
- You’ll also need a sharp saw, frag plugs, iodine solution, and aquarium adhesive.
How To Do It:
- Eliminate air bubbles by submerging the frag plugs in water for a minute or so to stop them from floating.
- Cut a few inches from the Frogspawn with your saw.
- Dab the frag with an iodine solution to prevent infection.
- Use aquarium glue to stick the frag to the plug or rock, keeping any slime away from any of your other corals and keeping the plug at least 6 to 8 inches away from the parent colony.
Place the frag in the same basic conditions as the parent colony but outside the safe buffer zone. Once the coral starts to grow, you can move it to its permanent location within your tank.
Health and Disease
Although Frogspawn corals are relatively easy to care for and don’t need specialized care, it’s essential to provide them with optimal conditions to prevent common health issues that could spell the end of your colony.
Here are some common health problems to be aware of that can affect Frogspawns.
These are brown flatworms that commonly attack tanks with very high nutrient levels, fixing themselves to the coral’s tentacles and cutting off the light. The coral rapidly suffers from depleted nutrients provided by the zooxanthellae and starts to die.
You can keep Acoel worms out by keeping your tank clean, quarantining new fish and live rock, and using wrasses or Blue Velvet nudibranch to control the worms.
Brown Jelly Infection
If the coral is injured or the water quality in your tank is poor, brown jelly infections can be a problem, rapidly turning your coral into a horrible brown jelly. If you don’t treat the infection quickly, your whole colony could die.
Start by immediately quarantining your sick coral and suctioning off the jelly, initially dipping the coral in an iodine dip of 15 ppt. Hopefully, prompt action will save your Frogspawn coral, but you might have to resort to amputating the entire infected area and throwing it out.
Availability and Price
As Frogspawn corals are so popular, you can find them in most good marine stores and online.
These corals typically retail for between $50 and $200, depending on the size of the frag, the variety, and the colors. More neon, brighter colors are pricier, but you could start with a small specimen, and the species’ rapid growth rate means you’ll have a healthy colony pretty quickly. Remember, too, that the Frogspawn coral branching variety is quite easy to frag, so you could create more colonies from an initial purchase if you wanted to.
Frogspawn corals are extremely popular, beginner-friendly corals that come in a plethora of bright, neon colors, making a fabulous display in any reef tank.
Many species of marine fish and invertebrates can live safely alongside Frogspawn corals. Still, you must remember to allow a 6 to 8-inch buffer zone between your Frogspawns and other species to keep them safe from this aggressive coral’s sweeper tentacles.
The Frogspawn coral is easy to find in good marine fish stores and online. Brighter colors are more expensive, but you could start with a small specimen and create new colonies by fragging from the original.