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h_tully

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About h_tully

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  1. Not necessarily (well, maybe not Brazil as such, but somewhere in the Americas): Trinectes maculatus (aka "Hogchoker") are on the permissible imports list - and if they are coming out of Bay and AI, there probably is a fairly good chance that they are imported. One of AI's info sheets ( http://www.aquariumindustries.com.au/Assets/24/1/FreshwaterSole.pdf ) lists two native species as well as T. maculatus, as species that they stock. I suspect care of all three species would be similar (as outlined by DFF)
  2. Thanks DFF. re: nitrite toxicity: you might be interested in the following excerpt: Fish disease: diagnosis and treatment - Google Books There is also a particular reason that I am personally convinced that salt is effective in treating/preventing nitrite toxicity (in freshwater fish at least): a couple of years ago, I had a batch of synspilum juvies (200 odd) : but no cycled tank to put them into. I came across some info that plants were very effective in soaking up ammonia and nitrate - so I put the juvies in a heavily planted tank 3 foot tank, fed them heavily, tested the water - and sure enough, ammonia was 0. It stayed like this for a week, and the fish were fine. Then, I noticed them looking rather lethargic, off their food and just generally shabby: I tested the ammonia, and TAN was still 0. I then thought mahybe its worth testing the nitrite - and it was above the maximum level of the test kit (5ppm). After some frantic searching, I came across the info in that book excerpt that I put the link to above: I threw in enough salt to reach 0.5ppt (10 X what they outlined , but still bugger all, really: 60g in 120L water), and by morning, they were bright and happy again and eating like there was no tomorrow. Nitrite was still high, but the fish just didn't seem affected anymore. I kept those fish in there until they were about the 5cm mark with a single hang-on filter, and all was well (and by a few weeks in, the tank and associated biofilter had cycled and both TAN and nitrites were 0) Looking back at some of my early failures in the hobby, I suspect that nitrite was more often than not the cause: I always used to test for ammonia, but I didn't even own a nitrite test kit until a few years ago. But, despite the above success - I'm still cautious about throwing marines into known high nitrite water. Should be OK in theory, but who knows what will happen? Cheers, h_tully
  3. So are you thinking that if I try this with the fish that this could/will kill them? (and even if not kill, then maim/damage?) I'm certainly not keen to do either. The article at Nitrite and the Reef Aquarium by Randy Holmes-Farley - Reefkeeping.com I found quite convicing: most info that I've come across that refers to the toxicity of nitrite to fish outlines the mechanism of toxity in freshwater, but doesn't consider what happens in the presence of chloride ions.
  4. Inverts I'd believe: but I've become sceptical that nitrite is as toxic to fish (under marine conditions) as conventional texts suggest. So, any thoughts on the fishless start, fishy finish style of cycling that has crossed my mind?
  5. Must admit - I haven't tested the nitrate recently, and this thought did cross my mind briefly : though when I tried the water change last time, it made no difference. There have also been times (in freshwater systems) when I've just let the nitrate build up for months on end with no observable detrimental effects on either biofilter or fish (my understanding was that nitrate was mainly only detrimental for fish growth) - don't know if that would be the case for marine systems though (I understand that lots of inverts are nitrate sensitive: but thought this might not be the case for a fish only system)
  6. I've come to expect the prolonged nitrite spike - but the thing I find really odd is that the resolution of that spike should be accompanied by ammonia consumption failure. It's happened now and pretty much was what happened at the end of last year. I kept a log both times of what happened, and it pretty much followed the same pattern: beginnings of nitrite spike at the end of week one; resolution of nitrite spike pretty much three weeks to the day from commencement, immediately followed by ammonia consumption failure. re: the further details: no water changes, no filter cleans. Temp very stable at 28.5 (last time I ran it at 30) - temp maintained by aquarium heater. pH stability, I must admit, I haven't been keeping an eye on (though last time, it never dropped below 7.8 ) I really am tempted to next time start off with a fishless cycling just until it gets to the point that the ammonia is being consumed rapidly overnight and then just add the fish: my understanding is that the effects of nitrite toxicity are really only apparent in freshwater, and that in marine conditions, the chloride ions stop nitrite from being biologically toxic to the fish. I have done this in freshwater tanks with no ill effect (by just bumping salinity to 1ppm), and then just let the fish sort out the cycle: which they have done with no problem. Though I'm a little worried as to whether or not this would work with a marine system. A mate of mine who doesn't believe in fishless cycling thinks that you need more to feed the microbes than just ammonia, and that you need "fish waste" to make a nice balanced stable biofilter community - maybe he has a point?
  7. About three weeks ago, I decided to attempt another fishless cycle: I pinched a small quantity of filter media from an established marine tank, and started adding Ammonium chloride at a rate sufficient to produce a 2.0ppm TAN reading. Within a week, I started to see nitrites forming. At this stage, I was adding enough Ammonium chloride to give 2.0ppm on a daily basis, and by next morning, the TAN was down to 0, but the nitrites were greater than the maximum reading (5.0ppm). This went on for another couple of weeks - then, mid-last week I do the usual check in the morning, but the TAN is at 0.5ppm. I didn't add any more Ammonium chloride, and then by the following day, TAN is back down to 0, but nitrites have come down to 1.0ppm. The day after that (when I've added enough Ammonium chloride to give 2.0ppm TAN again), the TAN reads 0.25. I go ahead and add enough to give 2.0ppm. Next morning, TAN is 1.0 and nitrites are down to 0. TAN is still 1.0 three days later. This happened at the end of last year when I tried this - just as the nitrites start clearing, the Ammonia consumption stalls - and stays stalled. Last year, I though I had overdosed on the Ammonium chloride or down something to kill off the biofilter - now I'm not so sure. Any thoughts on what's going on here? (and how I can stop this from happening in future?) Cheers, h_tully
  8. Hi, In the tank that I've been trying to fishlessly cycle, I noticed that the pH has dropped to around 7.8 (probably due to prolonged Ammonium chloride application - maybe this is why the biofilter mysteriously crashed?). I know that for freshwater, Sodium bicarbonate (baking soda) is commonly used to adjust pH: can I use this in a marine tank too, or will it stuff around with the composition of the ASW? If so, how do I bump the pH back up? Cheers, h_tully
  9. Sounds promising - where do I get these from? (are they widely available?), and what do they look like? (could I even slot some egg-crate into them?)
  10. Any thoughts on alternatives? Is it possible to get hold of thin, but rigid plastic mesh? (ie. thinner than egg-crate)
  11. Hi, I was just wanting to know if galvanised wire mesh is toxic to fish? - if not, can it be used as a tank divider? I realise plastic mesh would probably be much better - but plastic mesh doesn't seem like it would be rigid enough, and the groove that is there in the tank that I have (originally designed for a glass divider) is too thin to allow a sheet of egg crate to be put in. Cheers, h_tully
  12. To me, it looks a bit more Melanochromis-type shaped - though perhaps it is likely to be a hybrid? (quite possibly with some sort of Nimbochromis - the head has some Nimbochromis-like features, but as pointed out, the shape is not right, and the body markings don't look right to me for a Venustus - I can't recall venustus having pronounced egg-spots like that either)
  13. Personally, I found it very important to get an initial source of bacteria to 'seed' the filter with: even though these things are meant to be everywhere, when I tried to set up a bare tank, filled it with ASW, and then spiked the tank with Ammonium chloride - then waited (and waited; and waited), there was no formation of nitrites and no decrease in ammonia, even after 3-4 months. However, when I pinched some bioballs from a mate's tank: within a week I was seeing nitrite formation, and within two weeks (just before the major crash) the hang-on filter with associated bioballs was able to clear 5ppm TAN within 24 hours. I did have the temp at 30C to speed up the process (though note DFF's words of caution about doing this). I've been away for the past couple of weeks (and turned down the temp to reduce evaporation while I was gone), and was hoping that on my return the biofilter may have picked up again, but so far no luck (TAN still about 5ppm). I may have to try and go pinch some more seeded media again. re: the dead prawn method: is it likely there will be sufficient nitrifying bacteria to slowly colonise a biofilter? and would it therefore be better to leave the head/shell on if this was the aim?
  14. Thanks - good tip too about the dilution (hadn't thought of that). I am hoping it was the high ammonia, and not the salinity drop - mainly because I'm worried that if it was the salinity drop, then there may have been lots of osmotically related explosion of ammonia/nitrite converting bacterial cells (from which recovery might be a bit more difficult): I was hoping that they weren't so delicate though as to be damaged by a 2-3 ppt drop
  15. For the past three weeks, I've been trying to fishlessly cycle a marine tank (well, actually its been much longer than that - but three weeks ago I pinched some bioballs from a mate's marine filter - and finally starting to see some nitrite formation, and the beginnings of a cycle), and all was going well until early this week: basically, the ammonia was clearing from about 5ppm to 0 overnight, and I was just waiting for the nitrite to do the same (it was starting to drop to about 0.25ppm). Just when I thought it was all going to happen, I did two thing, one or both of which I think may have either killed, or at least suspended the cycling: 1) Because I had the tank at 30oC to speed up they cycle, I was having a lot of evaporation, so I topped up the tank with freshwater ie. I dropped the salinity from very saline: say 36ppt, to maybe about 33-34ppt in a matter of minutes. 2) I was reaching the tail end of my bottle of highly saturated ammonium chloride solution where there were lots of ammonium chloride crystals- so, while I added the right volume of what should have given me 5ppm, there's a chance that I OD'd on this. So, assuming one or both of these have done some harm to the biofilter (the ammonia has only maybe dropped from >8ppm to perhaps between 4-8ppm since Monday: but at those high levels, its pretty hard to be accurate on the colorimetric chart as to the exact concentration), have I killed it off completely, or will it slowly recover?
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