Plate Corals Dying: 4 Things To Check For Prevention

Corals generally need high maintenance to survive. However, plate corals require low maintenance compared to all the others.

If our plate corals are looking ill, we need to find out what’s causing them to look like that. Finding the main cause is the actual challenge here. 

How can you save your plate corals from dying?

There are 4 major issues that we need to keep in check if our plate corals start looking ill. They are water parameters, lighting, water quality, and pests.

Suppose these factors aren’t in alignment with the corals’ environment. Your plate corals could die.

You must be intrigued to know how to keep these 4 factors in check. Then, read along!

Consider the Type Of Plate Corals 

Before we dive right into investigating the possible cause, let me tell you something!

Plate corals themselves have lots of varieties. Among such variations, the most generalized ones are the long and short tentacled ones. 

Long tentacled ones tend to be more sensitive than short ones. They are also difficult to revive once they start getting adverse.

And, it’s unlikely that they’ll sprout offspring from their skeleton after they’re dead. 

Now, let’s dig into why our plate corals are not doing so well. 

4 Important Factors That Can Stop Plate Corals Dying

Plate corals comparatively require low maintenance. But there are certain ways you can take care of them routinely. This “routined care” will help prevent misfortunate situations. 

Plate corals, also known as fungia are pretty sensitive to 4 factors in the aquarium. The factors in order of importance are water parameters, lighting, water quality, and pests. 

What to do if we see our fungia shedding some tissues? 

We should immediately check these factors. They fluctuate a lot. Once the factors are set within their respective correct range, leave the fungia. We can expect them to revive completely with time.

But what if the coral eventually dies? Don’t take it out of the tank. Here’s why:

The skeletons sometimes sprout to give their offspring. So we better give the skeleton a chance to leave its babies.

Now, without further adieu, let’s dive into the main topic!

Factor 1 of 4: Water Parameters

The most important factor is salinity. If the salinity is off, pretty much all other factors are off. 1.023-1.025 is the best level of salinity. 

The next important parameter to check is alkalinity. We must reduce the alkalinity or increase it when needed. Try to keep it within 9-11. There are many kits available to check for alkalinity.

You can also use them to set the alkalinity right.

Next, check the magnesium level. 1350-1400ppm works great for most aquariums.

Get a test kit to check the level. Add supplementary magnesium if it goes too below the minimum range. 

However, magnesium levels naturally return to normal if it remains within 2000ppm. So, we don’t need to worry much about the high level of it.

If it exceeds the 2000ppm mark, we need to look for ways to lower the magnesium level.

Lastly, we need to check the calcium level in the water. It should be within 395-415. Choose only from the best calcium kits to get the best result. 

Accumulate the result for the last 3 factors. Then check the BRS calculator to determine the right level they should be kept in our tank. Then we can set them right accordingly with supplements. 

Factor 2 of 4: Lighting

Too much light can be bad for plate corals. It can cause them to stress quickly, leading to their death within a few days. 

On the other hand, too little light can gradually push them toward fatality. Within a few weeks, they would start to look ill. And within a few months, they’d be dead. 

Plate corals turn brown, and their tentacles seem to reach upwards or towards the light source if it is not enough.

They tend to shrink and lose their tissues when they get too much light. 

How can we fix this?

We should get a PAR meter that would help us handle the lighting with more accuracy. Hence, we should only get the best t5 bulbs to ensure a healthy life for corals. 

We also need to change the placement of the coral. We could place it closer or farther depending on its needs. 

Either way, it must be placed at the bottom of the tank. Make sure to leave it that way and not move it again. 

Factor 3 of 4: Water Quality

Water quality may deteriorate due to low maintenance or the unintentional addition of contaminants.

These may come from lotions, soaps or oils, or any such residues in our hands. It can also come from aerosols or other such chemicals near the tank.

These things can mess up the pH level of the water. 

But how do we identify our water’s quality? 

We need to look at the nitrate and phosphate levels using relevant test kits. There are many good phosphate test kits on the market.

However, you might want to think before getting a nitrate one. 

If the water quality isn’t up to par, change out the carbon filter. Our advice is to use a power filter this time. Wait for a day or two to see if things improve. 

If things don’t improve, get rid of the fancy mediums. Replace them with old-fashioned water changers. Get those water pollutants out ASAP. 

Do 30-40% water changes at a few days’ intervals and turn over most of the water in the tank.

Increase the percentage of water changes to 50-90% if things seem to deteriorate way too rapidly. 

Factor 4 of 4: Pest or Fungal Infections

Even if fixing the water quality solves the problem we should do this step.

For that, we need to check for pests or other unwanted elements. This can be done by dipping the coral in iodine-based dips. 

Next, we must look closely at the excretion (if any) from the fungia in the dip. If you find any, then you just saved your coral’s life!


Question: Are plate corals hard to keep?

Answer: Plate corals require the least maintenance out of all corals—especially the short tentacled ones.

However, they must be handled regularly with proper care to prevent plate coral from dying. 

Question: Do plate corals move?

Answer: Yes, they can move around or flip themselves upside down. If this happens, then you better get them out. This can cause the plate coral to die with time. 

Question: Where do I put my coral plate?

Answer: Fungia’s most suitable place inside a reef tank is at the bottom of it. Place them on an even grounded sand at the proper distance from other corals.

Check from time to time that it gets adequate light. Also, check that it doesn’t bury itself in the sand. These would prevent the plate coral from dying. 


Are you enlightened enough by this article? Then you better hurry and save your Fungia.

Don’t lose hope too soon. Fungia often comes back to life after they seem dead.