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Why Quarantine? and Questions and Answers Aquarium.Net Dec 96

This month Bruce tells us the hows and whys of quarantining fish, December 1996 Index for Aquarium Net, Aquarium Net has numerous articles written by the leading authors for the advanced aquarist

Why Quarantine?

This month we will go over how to set up a quarantine tank and introduce a fish into it.

Of course you have read last months article on how to increase the odds that your next fish purchase will survive. If you have not read it please go back and do that first. I mean it.

By the time you get a fish home it has been through a lot of stress and possibly exposed to many pathogens. One of the main purposes of the quarantine tank is to hold the fish in a tank that allows for easy observation. If the fish should show signs of parasites or other infections you can medicate with no risk of infecting the fish in your main tank. This is also a great time for the fish to get used to processed food without having to compete with tankmates that most likely are aggressive eaters.

Setting up the quarantine (Q) tank.

The first thing you need to do is decide how big the fish are gonna be that you plan to hold in the Q tank. Adult fish do not seem to adapt very well to captive life, they seem to have a hard time recognizing processed food. I suggest you only purchase juvenile fish and most of them will do fine in a 20 gallon tank. If the tank will have to be in an area like the living room you may consider something bigger with a nice stand. The Q tank does not have to be high tech and as a matter of fact I have found the lower tech the better.

The standard equipment will be a glass aquarium with a hood, light, heater, filter and something for the fish to hide in or behind. My favorite method of filtration for the Q tank is a sponge filter. A sponge filter can be either air or power head driven or even a sponge in a hang on power filter, the Aqua Clear filter line works great. You can seed the sponge by putting it in the filter or sump of the main tank for a week or two. It would be best if you had a couple of sponges so that you will always have one with plenty of bacteria. With this method you do not have to keep the Q tank running all of the time. If you see a fish at a store that you must have you can request that they hold it for a day. Go home and fill up the Q tank with fresh made salt water. Once the water is well mixed, at least 12 hours, and the temperature is right you can install the "seeded" sponge filter. Do not underestimate the importance of adequate hiding places. The fish must feel secure, you can do this with pieces of PVC pipe big enough for it to swim through even better is take a few pieces of live rock from the main tank. If you plan to get algae eating fish a rock or two with good algae growth will provide a grazing site. No substrate should be used.

Before running off to pick up the new fish run water tests on everything you can. Pay close attention to the alkalinity and make any adjustments necessary. Salinity should be 1.023-1.025 and temperature about 78º-80º. The new fish will need to stay in the Q tank for at least 20 days. The 20 day period is to ensure that the fish has no hidden problems. It will also give any parasites time to complete their life cycle. It is a good idea to have some AmQuel on hand in case you get a bit of ammonia. During the Q period it is important to have a regulated photoperiod. I suggest light timers with a 10-12 hour on period. The light cycle regulates hormonal output of the pineal gland in the brain that assist daily functions. Food should be soaked in one of the many vitamin supplements available. I have had great results using Selcon or Kent Marine Zoe for the algae eaters. After the Q period food should be enriched with vitamin supplements once or twice a week.

If all goes well and the fish is parasite free for 20 days we can begin the process to get it into the main tank. If during the Q process your fish develops any parasites you must medicate. My preference is to use copper and my brand of choice is Seachem Cupramine. I have had great results with it. If you do use a copper medication you must also use a copper test kit. Make sure that the test kit you get will measure copper in the recommended dose. After the fish is clean I suggest another week before starting the acclamation process.

Now that we have a clean healthy fish it is time to introduce it to the future aquariums water. If the tank is 10 gallons or less I suggest a complete water change with water from the future tank. If you are using a larger Q tank change as much water as you can. This will introduce the fish to the natural fauna of its future home away from the stresses of a new environment and aggressive tank mates. I like to leave the fish in the Q tank at least a week after the water change. If the fish develops any parasites you must go through the medication and water change process again.

Putting the fish in the main tank should be the same as when you introduced it into the Q tank. NO float NO mix, just a quick catch and release with the aquarium lights off. I feel that acclamation is one of those things that "we" have been doing forever and has never been questioned, until now. When I started in the pet shop business several years ago I floated fish bags for 10-15 minutes and then put the fish through a slow acclamation process. Bothered by the rate of fish losses in the first few days after a shipment I looked for a better way. Initially I tried every method I could get suggested to me. I kept notes and found little improvement with the different methods. Finally I tried the no float no mix technique and had wonderful results. It has been several years with 4 shipments of fish a week and I still think this is best for the fish. Invertebrates like shrimp, crabs and starfish do need salinity acclamation. The only reason we can bag fish is that CO2 from respiration lowers the pH. At a low pH ammonia is non toxic. When you open the bag you allow CO2 to escape, the pH will start to rise and this will allow the ammonia to become toxic. The longer the acclamation the longer the fish will be exposed to high ammonia. When transferring fish temperature and salinity acclamation in my opinion is simply not needed. Water temperature and salinity on the reef will change twice daily with the tide. The temperature swing can be over 10º with the tide change. Fish are routinely exposed to temperature changes as they ascend and descend.

To catch the fish I prefer to use a cup or a bowl to corral the fish into, I feel nets are to abrasive and should be avoided. Remove all the decoration from the Q tank and put the container in the corner. With your hand, of course on non venomous fish, corral the fish into the container and transfer it into the new tank. At this time you should have no medication in the water so you can just pour the fish and the water into the main tank. This should be done after the main aquarium fish are well fed and the lights are out. When you take the fish home from the store you should never introduce the bag water into the tank if at all possible.

After all of this it is not uncommon for the fish to pick up a few parasites after being introduced into the main tank. If you manage a good system with good water quality and offer a quality vitamin enhanced diet the fish should be able to handle it. If your fish should develop parasites in the main tank I suggest feeding one of the special medicated foods for parasitic infections. I have had good results with the Tetra brand. If the problem persists you may need to catch the fish and go through the Q procedure again.

Catching a fish in a decorated aquarium can be tough but that is another article...

Questions and Answers

I would appreciate any help

John (JP) Panteloukas Clearwater, Florida

A reply was sent to J.P. asking for more details about his system. The following is his reply.

Bruce, Sorry I was not clear on my pH. For the past 20 months my pH peaked in the day time at 8.4. Lately it has been peaking at 8.0 and after the lights go off it drops to 7.8.

Lighting is 510 watts VHO with Ice Cap ballast all on timers to simulate dusk to sunrise, URI bulbs super daylight-50/50-actinic. Total photo period 12 Hours. Kalkwasser strength is 2 tsp. per gallon of RO water, evaporation is replenished by float switch and power head. The main pump from a 20 gallon sump is gen-x. Tank circulation is provided by 6 Maxi-jet 1000 power heads, two of which are connected to spray bars that run in the back of the 150lbs of Florida live rock. By the way, my tank is a pentagon acrylic. Temperature is maintained by a west-coast chiller 1/4hp. Bio load consists of about 50 soft & hard corals, 10 med sized fish, 4 brittle stars, 2 cleaner shrimp, several astrea snails, red and blue leg hermit crabs. The pH is monitored by a pinpoint monitor and done manually with RedSea fish farm reef test. Filtration consists of wet/dry sump with in-tank over flow pre-filter, media is changed every week.

Any further help is greatly appreciated,

John (JP) Panteloukas Clearwater, Florida

J.P., The following question from Kevin is similar to yours and I talk a bit about the natural swing of pH in a healthy system. I feel that your fluctuations are no problem at all.

The problem you are having with a low overall pH is odd in a system with an alkalinity that high. first thing you should do is calibrate your pH meter. If you still get a low reading you should remove a few cups of water and let it stand in a open container for 12 hours of so. Test the pH right after removing the water and then after 12 hours. If the pH has gone up that indicates you have excessive amounts of CO2 in your aquarium and that will hold the pH down. I do not see a mention of a protein skimmer in your list of filtration equipment. Not only will a protein skimmer improve your overall water quality it will help to rid your water of dissolved CO2.

If you do decide to install a protein skimmer it will be best if all water passes through the skimmer before it flows through the biological filter. This will give the foam skimmer the opportunity to remove the organic waste before your filter processes it into nitrate.

If all else fails do a big water change, 50% or more. It is quite possible that you have an ionic imbalance and the easiest way to fix this is with water changes.

ttys Bruce Davidson Louisville KY Philoicthyoecetes

Question 2


My tank has been set up for just over 6 months and I have persistent problems with my pH levels. I am replacing 25% of the water in the tank as advised by my local aquarium dealer.

After my last water change on 28th October 1996 my pH level has been between 8.2 and 8.4.

Could you please give me advice on this matter?

Kevin W. Robertson Newcastle upon Tyne, England



The first thing you need to do is pick up an alkalinity test kit. This is a simple test and it should cost less than 15 bucks. Alkalinity oversimplified is the measure of your aquariums ability to neutralize acid or resist a change in pH. If your alkalinity is in the normal range the pH will remain stable. Stable does not mean that your pH will not change, as a matter of fact it should and that is a sign of a healthy system. I would like for your pH to stay in the range of 8.0-8.4. It should be at it's highest towards the end of your light cycle. It is not uncommon for a system with plenty of corals and or algae to drop down into the upper 7 range during the night. This is due to the CO2 released by algae. The "normal range" for alkalinity is 3-4 meq/l or 150-200 ppm CaCO3 or 8-11 dKH. These are the most common scales used. I would guess that you have a low alkalinity so it will be a good idea to pick up some form of buffer wile buying the test kit.

Tell me a bit more about your filtration.

Hi Bruce,

I recently purchased an electronic pH meter and digital thermometer and have just taken my second reading, the results are below.

Date pH Temp. 16-Nov.-96 8.1 73.9º 23-Nov.-96 8.2 70.4º

I have an under gravel filter with 2 powerhead pumps, one at each end of my tank on top of an air lift tube. As you will see my level seems to have leveled out and I am about to change my water again this next weekend.

I find I now have a problem with green algae. It covers all of the sand on the bottom of the tank to a depth of about 1inch, and though it looks unsightly I am told it is of benefit to my system if I can leave it in place, is this true and could you please tell me what causes this to happen?

Kevin Robertson


It looks like you pH is in the right range but like I said you do need to check the alkalinity. I would rather have those readings.

I do think your temperature is a bit low. Just about every animal that you will find in the pet shops is from tropical waters. At that low temperature the metabolism is reduced substantially. This will effect the immune system, the digestive system and many other functions. I think you should be in the 75º-80º range, your fish will be much healthier.

The algae problem you are experiencing is not uncommon with a Under Gravel (UG) system. The problem is that the UG catches all of the waste and process it into nitrate. Nitrate is a pretty good food source for algae. Another thing that is going is that the larger size coral gravel required for a UG system will allow detritus to settle in between the gravel. This detritus is loaded with phosphate and the algae can utilize that as a food source. The level of nitrate produced by your system can be lessened by the use of a protein skimmer. I would use the smallest powerheads you can to power the UG and get a quality foam skimmer. The phosphate introduced into your tank can be reduced by using only purified water for water changes and evaporation makeup. My preference for purified water is reverse osmosis (RO). Wile RO units are the best way to go you can get by with deionized water (DI). The Tap Water Purifier (TWP) from Aquarium Pharmaceuticals is a pretty cheap DI system. The TWP will cost you more in the long run but the initial cost is substantially less. The use of activated carbon and phosphate remover in your aquarium will help reduce the nutrients available to your algae now.

Is algae a problem? In a fish only system I have always said that there are only two kinds of algae, algae that YOU like and algae that YOU don't like. Personally I think that algae is a good thing in a fish only system. Algae offers a grazing site for most fish and it will be a breeding site for the little bugs that fish eat. In a tank that is to hold live coral the algae can become a problem as it will overgrow the coral and kill it.

ttys Bruce Davidson Louisville, KY Philoicthyoecetes

Created by liquid
Last modified 2006-11-23 01:36