How to kill Ich and marine velvet parasite in saltwater aquariums

saltwater fish ich cure and facts

How to kill ich and marine velvet parasites in a saltwater aquarium

Are your saltwater fish dying for no reason? Gasping for air and not eating? Not moving? Hiding? You may have Ich parasites or Marine Velvet in your saltwater aquarium.

Ich is a parasite and needs to be killed. Saltwater aquarium maintenance and care is what this blog is about.

There are MANY false statements about the ich parasite and marine velvet. Some saltwater aquarium hobbyists will say once you have ich in your saltwater tank, you will always have ich in your saltwater tank. This is FALSE!

I have done much research on ich parasites and marine velvet and have proven these false statements wrong, time and time again!

This nasty ich parasite is a silent killer

Ich parasites embed themselves in the flesh of fish and eats. After a few days the ich parasite drops off in the sand bed and encrusts in a cell.

The ich parasites multiply, releasing hundreds more parasites into your saltwater tank that seek out a fish to host and eat from the inside out.

Saltwater fish die quickly. The only thing that will save your saltwater fish is removing them from your saltwater aquarium and placing them in a separate quarantine aquarium.

What does Ich look like on your saltwater fish?

If your saltwater fish is infected with ich, you will notice what looks like salt on the outside of your fish. These “salt specs” are the actual ich parasites imbedded in your saltwater fish.

how to cure ich in saltwater fish in saltwater aquarium
What ich looks like on a blue tang saltwater fish

As the ich parasite embeds itself in your fish and starts to eat its flesh, you will see your saltwater fish zoom alongside rocks and the sand bed in an attempt to relieve itself of the pain, or to “scratch the itch.”

What if only one saltwater fish is infected with the ich parasite?

IF one saltwater fish is infected, the rest soon will be. You must remove all saltwater fish from your aquarium and treat them all. Treating just the infected fish will not remove the ich parasites from your saltwater aquarium.

Remember that ich parasites feed on the flesh of fish. In order to kill the thousands upon thousands of ich parasites or marine velvet in your saltwater aquarium, you must remove all sources of food for said parasite; your saltwater fish.

what do ich parasites look like on saltwater fish
Ich parasites are seen as white specs of salt on this Fox Face saltwater fish

Saltwater fish must be kept out of your saltwater aquarium for 6 weeks minimum to allow all ich parasites to die.

When there is no food source for the ich parasite or marine velvet (your fish), these parasites will die!

While in quarantine, your saltwater fish will be dosed with a mild copper solution by cupramine. This copper solution will kill the ich parasites and marine velvet on your saltwater fish as they stay in your separate quarantine aquarium.

You MUST QUARANTINE your saltwater fish in a separate saltwater aquarium with copper solution (cupramine.)

With no saltwater fish to feed on, the parasite will die in your main display tank.

This is how I KILLED the ich parasite once and for all! I learned the hard way by losing most of my saltwater fish when I was starting out in the saltwater tank hobby.

I have a book on Amazon that walks you through the entire process of killing the ich parasite and marine velvet if you need more info after watching this video.

How to kill ich parasites and marine velvet in saltwater aquariums

Saltwater ich and marine velvet and oodinium is a parasite not a disease. Ich and marine velvet must be removed permanently from your aquarium by letting it die by starvation: removing its food source; your saltwater fish.

Common WRONG INFO on Ich parasites

  • Feed your fish garlic and they will fight off the ich parasite
  • Raise the temperature in your saltwater tank to kill ich
  • Buy a wrasse saltwater fish to eat the parasites off your fish
  • Dose your saltwater aquarium with ich medication
  • Lower the salinity (salt level) in your saltwater tank to kill ich

All these statements on how to kill Ich Parasites are WRONG!


Feeding your saltwater fish well is not enough. I wanted to share what I have learned about ich parasites and marine velvet to help your saltwater fish and aquarium stay healthy.

I always keep each saltwater fish I buy, in the quarantine tank, with a mild cupramine solution, for 6 weeks, before adding them to the main saltwater tank, and you should too!

For an effective saltwater quarantine tank, the new saltwater fish must be kept for a minimum of 6 weeks in a separate saltwater aquarium, dosed with mild cupramine solution.

How to kill saltwater ich on your fish

Don’t waste your time if you can’t commit to this. Quarantine and treat the infected saltwater fish and any other potential hosts while allowing the display to go fallow (without any fish) until the pathogen or pest population dies out: 6 weeks minimum.

How did ich parasites get in my saltwater aquarium?

If you don’t quarantine your new saltwater fish in a separate tank with a mild solution of cupramine after you buy them, there is a good chance you infected your saltwater aquarium with ich parasites.

Ich parasites exist in the water column of all, or most, saltwater aquarium stores. Saltwater aquarium stores have one main filter system. If one tank is infected with ich parasites, then all saltwater fish in every tank have it.

If you buy live rock from the saltwater aquarium store that was sitting in infected water, that’s another way to bring ich parasites into your aquarium.

In some cases, like Cirolanid isopods, three months may be required. Copper (copper sulfate/copper citrate/ cupramine): Copper is a metal ion which is also basically a poison to any organism at a high enough concentration.

Copper treats most external protozoan and flatworm parasites. It is not very effective against crustacean parasites (parasitic isopods/copepods and the fish lice argulus/branchiurans) or marine leeches.

Copper is generally run at .2 ppm and only the salifert test kit we have found for the hobby level can accurately tell you where the levels are at within a respectable range. (API, red sea, Seachem don’t seem accurate enough or the colors are too close).

Saltwater fish become lethargic around .4-.6 ppm with copper sulfate and copper citrate and around .6 -.8 for cupramine. Some fish, such as seahorses/mandarins/lionfish/dwarf angelfishes/any already stressed or sick fish, are hypersensitive to copper, though we have pretty reliably treated those species with cupramine.

A very important note: Do not use ammonia binding compounds (amquel/prime) or UV sterilizer with cupramine and so it is imperative to turn those off when treating.

Copper overdoses include lethargy (fish acting dull, agitated, and unresponsive) anorexia (fish not eating), and even neurological signs like blindness.

Another important warning when using cupramine is that dosing directions on the bottle are not clear about the therapeutic dose. They explain dosing cupramine in terms of what volume to add to get to .5 ppm, however this dose is not necessary and actually getting close to a dangerous level for some saltwater fish. Therapeutic levels to treat most protozoan parasites is .2 ppm so cupramine should ideally be kept around .25-.3 ppm.

I have found that cutting the dose of cupramine in half is not only more than enough to treat saltwater fish infected with ich parasites, but it is much safer for them.

Purchase my eBook at Amazon on how to kill ich parasites and marine velvet in your saltwater aquarium.

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