Toadstool Coral Care Guide: Lighting, Flow, Feeding and Common Problems

If you are looking for a hardy coral that grows well and can make a real statement in your reef tank, it’s hard to go wrong with a toadstool.

Toadstool corals are one of the corals that I tend to recommend to newer reef keepers because they tend to be more forgiving. Unlike some SPS corals like Acropora, toadstool corals don't require the same amount of attention and once established can develop into an impressive centrepiece for your aquarium.

One thing that catches a lot of people out though, is that toadstools can look terrible when they're actually doing perfectly fine.

They close up. They get all polished up. They set sail. Sometimes they look like they’ve completely given up on life! They are usually just toadstools. So, let’s look at what they really need to stay healthy, how to place them in your tank and what to do when something doesn’t look quite right.

What Is A Toadstool Coral?

Toadstool corals are soft corals so they don’t build a hard calcium carbonate skeleton like Acropora, Montipora and other SPS corals.

Instead they have a thick fleshy stalk with a large mushroom head on top. When the coral is happy, hundreds of tiny polyps will come out of that cap, giving it that classic fuzzy or hairy look that makes toadstools so popular. There are lots of different types as well. Some have short polyps, some have long flowing polyps and colours range from greens and browns to stranger shades depending on the variety. 

They're also photosynthetic, meaning they get a huge chunk of their energy from the symbiotic algae living in their tissues.

Toadstool Coral Care Requirements

Don’t get hung up on hitting one particular number here. Experience has taught me that stability wins over chasing perfect parameters. A reef that sits at a slightly off number consistently is usually going to do better than a tank where you are constantly making adjustments trying to get everything “perfect”.

How Much Light Do Toadstool Corals Need?

Toadstools aren't particularly demanding when it comes to lighting. Generally, I would say low to moderate lighting, say around 50-150 PAR, is a good place to start. They can adapt to different lighting conditions but if you're bringing one home from a lower light system don't put it straight under your most powerful light and expect it to love you for it.

Give it a little time to settle.

When you’re using LED lighting, a good spread is more important than just cranking the intensity up as high as possible. Use your lighting app for the numbers but watch the coral.

A happy toadstool will generally have its polyps extended and a good full looking cap. If it keeps shutting down after you've adjusted the lighting, give it a while and ask yourself if you changed the lighting too suddenly and too much.

How Much Flow Do Toadstool Corals Need?

This is an important one. Toadstools like moderate, indirect flow. You want to see the polyps gently swaying in the current, not the coral getting hammered by a powerhead.

The reason flow is so helpful with toadstools is that they are constantly dropping their outer layer. Sometimes, you will notice a shiny film forming over the cap of the coral. It may look like there is something seriously wrong but this is usually just part of the normal process of shedding.

Good flow helps that layer peel away naturally and stops debris from sitting on the coral. If your toadstool is constantly leaning in one direction and getting blasted, move the powerhead or change the flow. You want motion not a hurricane.

Do Toadstool Corals Need Feeding?

Not necessarily. Toadstools are photosynthetic, so they get a lot of energy from their zooxanthellae, and you don’t have to target feed them every couple of days to keep them alive. That said, they can utilise nutrients and small particles in the water and occasional feeding with an appropriate coral food can be beneficial.

I wouldn't make feeding the main thing in terms of toadstool care. Much more important are good lighting, clean water and stable parameters. And beware the notion that “more food means more growth”. If you overfeed your aquarium, it can quickly become a problem with nutrients and algae.

What Is The Best Placement For Toadstool Corals?

Don't think about how big your coral is when you get it, think about how big it's going to get.

That little toadstool sitting in your frag tank may look harmless, but given time and good conditions, some varieties can get quite large. I'd give it a lot of space between it and the corals around it. Like other leather corals, toadstools can also be chemically aggressive and may release compounds into the water that may irritate other corals.

This doesn’t mean you can’t keep them in a mixed reef. Just need to give them some room and keep up the filtration and water movement. Running activated carbon can also be useful in a mixed reef where you are keeping a number of soft corals along with LPS and SPS.

Why Is My Toadstool Coral Not Opening?

This is probably the question I hear most often. The first thing I'd ask is: Has it recently been moved? If the answer is yes, give it time.

Toadstools can take days and sometimes longer to get settled in a new aquarium. They can stay closed during this period and form a coat of shine over the cap. Usually that is nothing to worry about. Or, the other possibility, is that it is moulting. You will typically see the polyps return as that outer layer starts to peel back.

I would resist the temptation to keep moving the coral around. Just give it a steady spot with good light and flow and let it be. Then start looking at your water parameters, lighting, flow and if anything in the aquarium could be irritating the coral, if it’s been closed for a long time.

Why Is My Toadstool Coral Shedding?

That's what it's supposed to do! It is completely normal for a toadstool coral to shed. The coral retracts its polyps and covers its surface with a waxy layer which it eventually sheds.

The first time you see it, it can look pretty scary, but don't strip the layer. Let the coral fall off naturally. However, if the film is going to last a while, you can use a turkey baster or something like it to gently blow water over the coral. This may help break up the material without harming the coral.

Why Is My Toadstool Coral Shrinking?

Again, don’t go jumping to any conclusions. Toadstools naturally contract when they are shedding, and they can also shrink if they are moved or if there is a change in their environment. If it's only been going on for a few days, I'd give it some time.

That would be the time I would start to look into it if the coral stays really contracted for a long time. Test the temperature, salinity, alkalinity and other water parameters and consider if there has been any recent change in the aquarium.

Why Is My Toadstool Coral Turning Brown?

Color changes can occur for a variety of reasons, including changes in lighting, nutrients and general stress. For example, don't make another change just because the coral looks different if you have just increased your lighting. Give it time to settle in.

The same goes for nutrients. Toadstools don't generally require an ultra low nutrient environment. Removing nutrients from a reef too aggressively can be a problem for corals. When a change occurs, make one change at a time and allow the tank to respond. That is one of the best pieces of advice I can give any reef keeper.

Summary

Toadstool corals are one of the easier soft corals to keep, but don’t let that fool you. Give them good light, moderate flow, stable water parameters and room to grow and they can make a great feature in your reef. And remember: if your toadstool suddenly closes up and looks like it was covered with wax, don’t panic. It’s probably just having a bit of a spring clean.

Patience is a virtue in reef keeping, like in so many other things. Maintain your conditions constant, don't make five changes at once and give the coral time to settle. Most of the time it will pay you back by opening up again and looking better than ever.

If you have trouble with a toadstool coral or are unsure where to place one in your reef, contact the team at Reefco Aquariums. We are happy to help anytime.