It is not as difficult as it sounds. In fact, I found it to be quite easy. When I first noticed that my Tang had Ich, I was scrambling to read every article I could find and visited several forums seeking advice. I was in sheer panic. I hope this sticky saves some members time from doing all that searching. There are 3 or 4 proven methods to kill ich and hypo is only one. I found it to be very easy, and hopefully you will too. One thing that I STRONGLY recommend is a recently calibrated refractometer. A swing arm style hydrometer is no good for this IMO. Your goal with hypo is to slowly lower the salinity in your QT from the normal 1.026 down to 1.009 over the course of several days. This salinity forces the ich cysts to go through osmotic shock and literally explode. Achieving and maintaining 1.009 is extremely vital to this process. Anything higher than this might allow the ich to survive and anything lower can stress or harm the fish. While maintaining this salinity is very important, if you are going to error, it is better to error on the low side. Most species can handle a slightly lower salinity (1.008), but you do not want to go above 1.009 which risks allowing the cysts to hatch. The timing is also vital as you need to make sure you get the ich as it passes through ALL of it’s life cycles. Hypo is only effective at killing ich at ONE of it’s life cycles, so it’s important to give it ample time for all ich to pass through this tomont stage. Most people recommend 4-6 weeks from the last time you see symptoms. I will recommend a conservative 6-8 weeks. I personally went with 5 weeks in hypo (I started my calendar after the last symptoms of ich which was actually about 4 or 5 days into the treatment), then I took the sixth week to slowly raise the SG back up to 1.026 very slowly.
Here is what you need: a running QT, a couple buckets of RO/DI water, recently calibrated refractometer, and patience.
Fortunately, I quarantined my Hippo Tang right from the LFS and never introduced him into my DT. Day 2, and I saw white spots all over him and immediately identified it as ich. After deciding on hypo for treatment, I removed water from my QT and replaced it with RO/DI water bringing the SG slowly down to 1.022. The following day (around the same time), I removed QT water and replaced with RO/DI lowering the SG to 1.018. Day three, down to 1.014… Finally Day four, down to 1.009. In more severe cases, you may speed up this process to bring the SG down quicker if you deem it necessary to quickly treat a severely infected fish. However, you also want to be cognizant of any undue stress that you might bestow upon your already sick fish by potentially forcing him to acclimate to lower salinity too quickly. Only you can diagnose your patient and make that decision based on your observations and experience. As you’ll read later, however, it is not acceptable to raise the SG quickly after you’ve completed the treatment.
Once down to 1.009, I then made a large batch of 1.009 water made mostly from discarded water from my DT. Keeping in mind that you will be diluting your DT water by half… a 10 gallon water change can yield 20 gallons of 1.009 water when diluted with 10 gallons of RO/DI water (use that refractometer ).
Raise the temp to 82 degrees. The ich lifecycle will speed up at this temp and go through their stages faster.
For the first week, I did a 20% water change every day and a 50% water change every third day. The second week and thereafter, I did a 20% water change every other day and a 50% water change once a week. Most people recommend daily water changes, but I couldn’t keep up. I did, however, check the SG at least twice a day and topped off as I needed with RO/DI water. I topped off in the morning and the afternoons. While doing your water change, do your best to siphon out any leftover food or detritus along the bottom of the tank.
I also wanted to keep him well fed, so I chose to feed everyday. I mixed up his diet everyday to give him variety. I soaked nori in Garlic and had that in there almost constantly for him to graze. I fed him Formula 2 with gel binder which I also soaked in garlic. And I also fed him a good quality flake food. The diet you choose to feed will be dependant on the fish you are treating. So do your research and be sure to feed your sick lil guy the best and healthiest diet for his species. I like to soak in garlic as there have been some connections with garlic potentially helping a fish kick ich. There are several theories as to why garlic is deemed beneficial, none of which I am going to get into. Find a delicate balance with your feeding. You want to keep them well fed, but you do not want to overfeed and pollute the tank. the final week in QT, I backed off the feeding to every other day to mimic the conditions which he’ll see in the DT. This will give him time to adjust to the DT feeding schedule without having to compete with the other fish for his meals.
I tested for Ammonia every day for the first week, then dropped off to every other day for the second week. The third week, I dropped off to even less frequent testing… to maybe only a couple times a week. I had a Seachem Ammonia Badge in there to give me an idea of the Ammonia levels. These badges shouldn’t be relied on for accuracy, but can give you a broad overview of the NH3. You really should be testing every day or at least every other day. I got lazy into the third week. Thankfully my biological filtration and water changes kept my NH3 under control. Maintaining low nutrient levels is always preferred by way of good water husbandry, however the use of conditioners and/or buffers, such as AMQUEL, is certainly acceptable. I’d even suggest that you pick up a bottle “just in case.”
I kept a flashlight next to the tank and watched him at night from time to time. While looking healthy during the day, the fish seems to be more stressed and infected at night. You want to check for white spots while he sleeps and heavy, labored breathing.
After 5 weeks without symptoms in hypo, it’s safe to start bringing the SG back up to 1.026 slowly over the course of several days. Instead of making a batch of 1.009 this week, I made a large batch of 1.018. Day 1 of Week 5, discard QT water and replace with 1.018 water to slowly bring the SG up by 0.002. Continue to raise SG 0.002 each day until you get up to 1.026. Keep him in the 1.026 for a couple days to observe and then he’s ready to go into the DT.
It is very important to raise the SG VERY slowly. you should not exceed 0.002 per day or you could risk exposing your fish to osmotic shock potentially killing him. Please be patient and conscientious with this process.
Setting up a QT
Use a small simple aquarium. I used a 20Long, but in hindsight I could have used a 10. Keep in mind that the smaller the tank, the greater the need to be diligent with your water husbandry. Not that having a larger QT is an excuse to get lazy, but smaller tanks will get overcome with toxins and nutrients quicker than a larger tank with more water volume might. Of course a larger tank means larger water changes. Some people say to keep the QT proportionate to the size of the DT. About 20% is recommended, but I’m not completely sold on that theory. I do, however, think that using an aquarium is a good idea versus a rubbermaid or a bucket. The glass aquarium allows you to observe the fish easily through the front and sides. I painted the back and bottom black to cut down on reflections and comfort the fish.
You’ll need a simple HOB filter, a heater and an airstone. On a 20, I used a small powerhead; but on a 10, it might not be needed. Decorate the tank with various pieces of pvc to give the fish some hiding spots and feel comfortable.
Take the clean sponge from the HOB and set it in your sump/fuge for a few days to seed the sponge with beneficial bacteria to start your biological filtration in your QT.
For ich, you want to raise the water temp to 82 and speed up their life cycle.
I can’t take credit for any of this as I took most of it from 2 great articles written by Steven Pro (linked below) along with other credible sources.
Article from ReefCentral linked HERE
In hyposalinity the normal salt content of the tank is reduced by over half, that is from normal 35 ppt to 16 ppt, which corresponds to a specific gravity of 1.009. The treatment is done in stages. On day one RO/DI is used to replace hospital tank water till specific gravity falls to 1.022, day two it is reduced to 1.018, day three 1.014, day four to 1.009. This last salinity is very important. If even .001 unit high the ich can survive and if too low the fish can be harmed. That is the reason a refractometer is used. Once the specific gravity is down it is wise to make a batch of saltwater up that has a salinity of 1.009. This is used for daily water changes to reduce the chance of ammonia or nitrate buildup during treatment. The low salinity is maintained for a month. The salinity is then increased, but even slower. Raise it 0.002 units each day until 1.026 is again reached. Once at normal salinity the fish may be returned to the display.
Hopefully you found this post to be helpful. Good Luck!