So we get a LOT of questions on how to properly treat diseases in marine fish. The most common of all is Marine White Spot (Cryptocaryon Irritans) also known as saltwater ich/ick disease. For this post we will focus only on white spot, its life cycle and how to treat it. We will touch on other common diseases such as flukes, velvet, brooklynella and intestinal worms later.
So what is marine white spot?
Marine whitespot is a protozoan parasite, it is one the most common diseases found in almost all home aquariums, if you have purchased a fish with out first quarantining it. Chances are you may have it in your system already! It is ALWAYS advisable to quarantine your fish first before adding in to your main display tank.
There are several stages of Cryptocaryon Irritans and its life cycle in your tank, where at times you will see them on your fish and then they will go away. IF YOU HAVE HAD IT IN YOUR TANK YOU WILL ALWAYS HAVE IT UNLESS TREATED. They are only ever noticed when they are on the body of an affected fish, which have already buried in under the skin, have become pregnant and caused a lesion (similar to a human mosquito bite). All other times they are either still in egg form(cyst), free swimming, which is completely invisible to the naked eye, have just attacked the skin of a fish or hidden within the gills of a fish. A full cycle from being a cyst to completing its life cycle can last anywhere up to 10 weeks, which is why we see many tanks where it will come and go.
Some common misconceptions on how to treat the disease DO NOT WORK. Save the garlic and ginger for dinner. These do not treat whitespot, rather we have found that adding a garlic supplement to our fishes food has helped to entice fish to start eating once it arrives, this is as much help as garlic will do.
3 100% PROVEN ways to properly treat white spot.
Copper is and always will be our go to for treating the disease, but not all fish can handle copper treatments. Be wary of scaleless fish and angel's as they do no like heavy treatments of copper. For these guys you will need to add the copper in to your quarantine system slower over the course of a few days to get them acclimated to it or use one of the other treatments below. Copper will also kill inverts and corals, they can not get infected by Cryptocaryon Irritans but can be harboured into your system by the water they are transported in.
Treating new fish.
In a quarantine tank you will need to treat your new fish for a minimum of 2 weeks while maintaining your copper levels at 0.15 mg/l to 0.3 mg/l, use a good quality copper test kit. In the tank you will want plenty of oxygen in the form of an airpump with airstone/sponge filter, heater, some form of existing media for nitrification and some hiding spaces (PVC pipes work well). You will want to keep these guys in a low stress, quiet environment. No light is required during this time. They will do well with a variety in their diet of frozen and dry food soaked with a fish food enhancer/vitamin. Dry and frozen food can sometimes lack essential omega 3 fatty acids and other nutrients lost in manufacturing/freezing/storage which is why these enhancers and vitamins are an essential part to add into your fishes diet. Once you have treatment it is advisable to clean out your tank for any traces of copper that may still be in the system by using a treatment or carbon.
Treating fish from your display tank
Treating fish as above will be fine if you run a Fish Only With Live Rock (FOWLR) system. But if you have corals and inverts (or plan to later) you will want to treat in a separate hospital/quarantine tank as copper will soak into live rock, media sand etc. and will leach out over time. For tanks with corals and inverts already you will want to catch all fish out of the tank and treat as above. You will also need to keep your main Display Tank (DT) fishless for minimum of 10 weeks, this will ensure any left over white spots will have finished its life cycle and have died off by not finding a fish as a host. You will want to quarantine all new additions(corals and inverts included) to your tank to ensure you never have the issue again.
Products we have used with success:
Ultimate Aquacare (now Quantum) Copper Treatment
This is the process in which we will lower our specific gravity in our water to sg 1.008-1.009 and hold it there for a minimum of 4 weeks from when the last spot has been seen on a fish. This will not work for tanks with corals and inverts. You will also need to monitor PH during this time as there will not be enough salt and trace elements to maintain stable PH. Do not raise or lower you sg by more than 1.002 a day, as salinty shock can stress and kill the fish.
3) Tank Transfer Method (TTM)
This is the process in which we will need two separate holding tanks. You will need air pumps, air stone/sponge filter and an ammonia binder. You will start by putting the fish in to hospital tank 1, leave the fish in there for a MAXIMUM of 72 hours. When the transfer is to happen, you will need to ensure that hospital tank 2 has matching PH and SG. Take fish from tank 1 and transfer to tank 2. There is an option here to have an extra bucket of water to give the fish a quick fresh water dip to avoid contamination, also use different nets for each tank. After this, you will need to ensure that tank 1 is thoroughly cleaned and disinfected with bleach or vinegar and completely dried of any contaminants ready for another round of transfer. You will need to repeat this process a minimum of 4 times, with each time not exceeding 72 hours. This will ensure that white spot does not have enough time to properly attach to a fish and reproduce.
I hope this helps you in educating how Cryptocaryon Irritans works in a marine system and how to treat your own fish.