Maracyn Two Question (difference between FW and SW versions)

[vaporize]

Hi Lee,

I think I remembered reading that the normal Maracyn Two for FW is actually the same as Maracyn Two for SW except the that SW version is twice the dosage of FW one, is this true?

I have access to a lot of Maracyn Two for FW but not the SW version due to the Canadian FDA (or similiar) ban on the medication (so stores took it off shelf).

[leebca]

Sorry to hear about the regulatory restriction.

The only difference between the two Maracyn Two products is that the one for SW fishes contains an appetite stimulant -- Vitamin B12. The FW Maracyn Two does not contain this Vitamin.

Both should be administered at the same dosage.

[goblin072]

I take it that minicycline suppresses the appatite of marine fish and not freshwater. Otherwise why not add the vitamins to both and then lable the product marine/freshwater. It would save confusion of people looking for it.

I avoided the freshwater one until I found out they were pretty much the same except the vitamins.

[hyde]

Sorry to hear about the regulatory restriction.

The only difference between the two Maracyn Two products is that the one for SW fishes contains an appetite stimulant -- Vitamin B12. The FW Maracyn Two does not contain this Vitamin.

Both should be administered at the same dosage.

Lee,

I'm a bit confused and in need of help.

I am treating an Acanthurus leucosternon (Powder Blue Tang) and an Synchiropus splendidus (Green Mandarin) for ich with Ich Cure in a 20 gallon hospital tank (only med I could readily find). They got pretty far before I got the nerve to try to get them out of my 75 gallon reef tank. They are the only two fish I had in there. I am on day two of the three day dosing and this afternoon I saw the tang's tail fin disintegrating at the corners.

The only thing I can think of is tail rot. I went out and looked for Maracyn 2 per some of your posts and was unable to find it as I live in El Salvador and we are lacking in some comforts. I purchased Minocycline in 100 mg capsules for human consumption at a drugstore, but when trying to figure out the dosage I ran into this post. I have seen the SW and FW versions side by side at (Mardel Maracyn-Two - Saltwater - Fish - PetSmart) and indeed the Minocycline content is double in the SW version as vaporize states here. What I cannot confirm is if the dosage instructions remain the same for the SW version, in effect delivering a double dose.

Here's the question... Can I start the antibiotic while treating with Malachite Green/Formalin? and could you help me determine the proper dosage?

Best regards,

John

[leebca]

The antibiotic in Maracyn Two is systemic. That is to say its benefit is for infections that are internal to the fish. Fin/tail rot is not systemic (not internal). An antibiotic for external infections would be best. Still Maracyn Two would be fine. Beside systemic, it targets Gram Negative bacteria.

The difference between Two for saltwater fish and One for freshwater is an additional additive in the Two to improve hunger. I don't know for sure if it works, though, so Two for saltwater fishes or fresh is okay.

As for Maracyn One, that is a different antibiotic and it targets Gram Positive bacteria. Most ornamental marine fish infections are Gram Negative.

The human digestive track is much different from that of a fish. So a pill meant for swallowing and a pill meant to added to water might be quite different. By this I mean I don't know if Mardel has put any other ingredients in their product or if the form of the antibiotic is special, for any reason.

That said, there is no way I could help make the transition from a human drug to a fish. Even the human pill may not be 100% antibiotic, but a combination of binders and things which just complicates matters further.

Lastly, the combination of drugs is something that the drug makers know. With adding the above unknowns to the situation, I don't think even the makers of the drugs know if they can be combined. But for sure, I don't.

Wish I could be of more help.

[hyde]

Thank you for the quick response Lee. No need to apologize, your publications on this site have been of incredible help in understanding the fish side of the hobby.

We are quite used to "shooting from the hip" with DIY additives and meds down here due to the lack of locally available products. Since many of us travel to the US every so often, we usually have access to things with some notice. However, in the case of medicines, expiration dates become an issue so nobody keeps them locally and by the time someone brings them it's too late.

I will go ahead and take the risk, I just wanted to make sure I wasn't committing some horrible no-no. I would rather have the fish die because I did too much than because I couldn't make a decision... I'll let you know how it went.