Treating DT with Prazi, strange series of events

[whoopadeedoo]

I added Prazi (2.5mg/L) to my reef tank to kill a bad case of flukes causing some fish (angelfish in particular) to stop feeding and do their head shakes and shrimp molestation. Five days into "round one," the fish improved and all started eating again.

Day seven, did a large water change and added round two (same dosage). Three days into round two, fish (angelfish in particular) still feeding but seeking the shrimps more. What's weird though is my female fairy wrasse (which definitely had flukes that I thought I killed off in round one) suddenly has labored breathing and probably won't make it. The wrasse was fine even when it had flukes and going through round one.

What do you think is happening to the wrasse? Did some fluke eggs hatch and re-infest prior to round two? Did the second dose harm my wrasse?

Water parameters are fine. In fact, the alcohol from prazi acted like a carbon source and fostered bacteria that has kept algae/cyano population really low and water is quite clear. Water was slightly cloudy for a day after first dose over a week ago. Skimmer is turned off by necessity, but I have two Tunze streams at full blast.

[Reefing Madness]

You'll want to shoot Leebca a message to get this one answered.

[leebca]

It's not clear to me the exact product you added to the DT. "Prazi" is short for praziquantrel and it is also a brand name. People also use "Prazi" to mean a group of other products. Unfortunately, all of them are used for treatments of various types of parasites and flukes. These products are dry so I wonder what it is, with alcohol, you are using.

If it is praziquantel, then adding it to the DT in a marine tank is generally not a good idea. It ia a freshwater drug treatment and it works best in freshwater. It is really used best in ponds. One of its features is that it doesn't require water changes or any kind of removal when used in ponds. So the experience you are having indicates this isn't such a good thing for your marine DT. It has never been tested for use in the pesence of all types of marine life. Yet, there are those who 'claim' it is reef safe. We know it doesn't disrupt the biological (marine) filter, but what other effects it has on the micro life has not been documented. I use it quite often, but as an internal treatment (added to the food) and can be administered like this without moving the fish from the DT to a QT. I prefer to use other products as a 'tank treatment.' Those products are specifically made for marine QTs.

Since it kills flukes and certain types of pods, it may well kill or alter the life forms in live rock and living substrates. If your DT didn't contain live rock, then it might be something to try, but you're on experimental ground as far as this hobby goes. Understanding all this, you might be experiencing some of the 'unknown factors' associated with this product.

It has no known adverse effects on higher life forms (marine fish) as far as known, so I don't think it would be the cause of the wrasse's current problems. Maybe a coincidence. However, the second dose does concern me and whether or not an overdose has been made. The Prazi could be affecting other things in the tank which could lead to problems with the wrasse, or an ovedose could be affecting this fish. But let's not forget the alcohol. The fish might be having problems with that particular ingredient AND/OR the changes made to your system by its addition.

Praziquantel is a powder and added as a powder to ponds and marine quarantine tanks for treatements. One product called "Prazi" is actually a one-time addition, so I don't understand your reference to 'round two' which implies multiple treatments. I'm not sure where the alcohol comes into play and makes me wonder if the "Prazi" you are talking about isn't something different than what I've been rambling on about above. Adding alcohol is not something I would recommend for average hobbyists. It does foster a different group of marine bacteria and experiemnts with it has sometimes led to bad or at least, uncontrollable results. Advanced hobbyists do experiiment with alcohol (of which there are many different kinds).

Can you provide an Internet link to the product? Can you provide more info about the product. What directions are you following for it use?

The last thing I gathered from your post is that you have or see cyano in the tank. This leads me to suspect there may be other things going on with water quality and tank setup.

The way forward is to immediately make a HUGE water change (over 85%). Since this is such a large water change, follow the guidelines in the sticky post on making water changes. Repeat this same HUGe water change again in 3 days. These water changes are specifically to remove the product, so don't add it back in. Get the skimmer running again as soon as you can and if you use carbon, change it out now and again after the second water change. If you don't use carbon, get it and use it.

I think the above is about all I can say with the information provided so far.