Provide relief your freshwater or saltwater aquarium fish from bacterial infections with Mardel Maracyn. This specially compounded broad-spectrum antibiotic contains the active ingredient erythromycin in a fast-dissolving powder form to deliver effective treatment and control of a number of pathogenic bacteria associated with ornamental fish disease. Mardel Maracyn is effective against gram-positive pathogenic organisms.

Mardel Maracyn is recommended for the treatment and control of body fungus "columnaris" fin and tail rot, popeye and gill disease in freshwater (tetras, cichlids, livebearers, catfish, and goldfish) and saltwater (angelfish, clownfish, damsels and other common species) caused by Flavobacterium columnare, Haemophilus piscium, Aeromonas punctate, Aeromonas hydrophila, and Cytophaga aquatilis bacteria.

Use 1 packet per 10 gallons of water.

Mardel Maracyn is non-toxic to invertebrates. Follow dosage directions as detailed on the product packaging.

Directions & Dosage
Add the contents of one package per 10 gallons of water and repeat every 24 hours for 5 days. Repeat this 5 day treatment only once if needed.

Important: Treat for 5 days even if visible signs disappear. Maracyn may be used concurrently with Coppersafe, Maracyn Two or Maracyn Oxy. Maracyn will not harm invertebrates. Maracyn may cause excessive foam production in protein skimmers. Stop use of skimmer during treatment if excessive foaming is a concern.

Note: Consult a veterinarian or fish expert for assistance in diagnosis of disease causing organisms and treatment options.

Frequently Asked Questions regarding Mardel Maracyn
Q. Will I see an ammonia or nitrite spike after using Maracyn?
A. Almost all nitrifying bacteria are gram-negative and not adversely affected by Maracyn and you should not see either an ammonia or nitrite spike.

Q. I've used Maracyn/Maracyn Two twice now for two full treatments and it does not appear to be working, can I treat a third time?
A. That would indicate that the source of the problem is not affected by the active ingredients in Maracyn/Maracyn Two. In this situation, rather than repeating an ineffective treatment, using a medication with a completely different active ingredient might be the best solution. So, if Maracyn was not effective, try Maracyn Two and vice versa.

Q. Can I use Maracyn and Maracyn Two simultaneously?
A. Yes. Maracyn targets gram-positive bacteria and Maracyn Two targets mostly gram-negative bacteria. They may be used in conjunction with one another. However, in doing so, the balance of beneficial bacteria in your aquarium, including nitrifying bacteria to remove ammonia and nitrite will be adversely impacted. Fritz strongly recommends the following: *For freshwater aquariums, have on hand and ready to use FritzZyme 7 to replace the nitrifying bacteria that naturally remove ammonia and nitrite and FritzZyme 360 to replace the other beneficial bacteria in the aquarium. *For saltwater aquariums, have on hand and ready to use FritzZyme 9 to replace the nitrifying bacteria that naturally remove ammonia and nitrite and FritzZyme 460 to replace the other beneficial bacteria in the aquarium.

Q. Can I use Mardel Maracyn at same time as Prazipro?
A. Combining treatments will be fine. Just be sure to monitor your ammonia levels while using any treatment.

Q. Will the addition of beneficial bacteria interfere with the Maracyn?
A. No, the introduction of nitrifying bacteria will not interfere with the Maracyn, but you may want to consider a chemical ammonia remover, like Fritz ACCR to help alleviate the unexpected ammonia spikes.

Q. Can I use Mardel Maracyn and Pimafix simultaneously?
A. Yes, they can be used together. Just always be sure to keep an eye on your ammonia when using any treatment.

Q. How do you recommend using/dosing your beneficial bacteria during a 5-day Maracyn/Maracyn Two regimen?
A. Using the maintenance dose should be adequate, which is 2 oz per 10 gallons.

Q. I think my fish has a bacterial infection, how do I know which product to use, Maracyn or Maracyn Two?
A. If you see specific symptoms mentioned on the packaging or enclosed brochure (body fungus for Maracyn, Fin and Tail Rot/Popeye/Dropsy for Maracyn Two) treat accordingly. However, if the symptoms are less specific and harder to identify, start with Maracyn Two (which is a broader spectrum product) before using Maracyn.