Help Setting up a hyposaline QT Tank

[tangaeric]

Dear all,
I have a few questions concerning the setting up and maintaining of a QT tank for hypo treatment of new fish. I catch all new fish myself in the Indian Ocean in front of my house in Tanzania and after having had an ick problem in my 2000 gal reef tank and finally cleared it (following Terry's directions), I am 'trying' to treat all new fish preventively for ick before introducing them into the display. I have made two attempts but have had many water quality problems and killed many fish. My questions are;
1. I understand that it is a good idea to have a QT tank up and running at all times. Since I will be treating ALL new fish preventively for ick in hyposalinity, would it be better to maintain the QT tank running in hypo at all times and slowly introduce the new fish in there or maintain the QT tank at saltwater salinity and drop it to a SG of 1.009 each time there are new fish in there? My biggest concern is what happens to the bacteria in the filtration system during such drastic salinity changes. I wouldn't want to kill the bacteria in any filtration system after the many days is takes to establish them.
2. Would it be a good idea to maintain the QT tank up and running at all times WITHOUT drying them out and starting all over after each batch of new fish has been treated and moved to the display?
3. Is a trickle filter suspended above the QT tank and a 100 gal/hr sub. pump pushing water through it enough to form an adequate bacterial colony to keep ammonia and nitrites in check? I used to have a sand bottom and a plastic basin filled with sand holding an inverted funnel and an airstone in it but both the sand bottom and sand in the basin developed a foul smell over time. I attribute it to the fact that I did not sterilize the sand (it was not live sand but beach sand that dries for many hours daily) before using it and probably the bacteria in there were dying in hypo. Now I only use the trickle filter and sub. pump to circulate the water through the filter.
All your help is much appreciated.
Eric

 

[beth]

You'll want to introduce the fish to the QT with normal salinity parameters in place, and then, over a 48 hour period, gradually reduce the specific gravity to 1.009. Fish can not just be introduced to hyposaline conditions. Assuming you have an established and cycled QT, then the bacteria colonies should be fine. Following the 3 weeks in hyposalinity, you will need to raise the salinity back up to the same parameters as the conditions in your main tank. Taking a bit longer [5 days] to do this. Leave your fish in QT for yet another week. If everything is good at that point, then you can introduce them to your main tank. It would definitely be a good idea to maintain a QT up and running full-time. You will need to continue “feeding” the bacteria colony in the QT when fish are not in there, otherwise the bacterial filter will diminish or die off.
A QT should not have sand or any substrate in it. If your fish get sick and you need to medicate them, sand, porous rock, etc., can absorb some meds, rending medication therapies less effective. Thus, in a QT, you will want a bare bottom, with either fake rocks as hiding spaces for fish, or PVC.
There have been a good deal of discussions on QT recently. I’d suggest that you do a quick search here in the Disease Forum, you should find a good deal of info.
Must be nice to have a 2000 gal tank! Do you have any pics?

 

[tangaeric]

Hi Beth,
Thanks for the detailed input. I have actually been introducing my fish into a hypo tank over 24 hours, not directly in.
I will modify my application to what you recommend. Thanks.
Yes, it is nice to have such a tank but WOW!, what a handful and more when you have ick problems in there!!!! I had to dismantle the entire reef to catch every single fish so that I could leave the tank fishless for 30 days!!!
I don't have any current pics so I'll have to work on that.
Thanks,
Eric