chriscoli
Administrator
I have a tank that I've been having a bit of trouble with lately....and had an epiphany this evening about what may be contributing to my problems.
Here's the situation: I have a tank rack with 16, 10 and 15 gallon tanks, all filtered with HMFs, and until now, they've been rock solid and seem to handle whatever nastiness comes their way. I have one 10 gal tank (with one pair of Pelvicachromis and a handful of fry) that keeps having both bacterial bloom and issues with a successful nitrogen cycle. I've re-seeded the filter from other tanks, I've given it more frequent waterchanges and I even (gasp) added various bacterial products to it. But still every few days I walk by and see the female Pelvicachromis swimming in one place mid-water, staring straight ahead with fins clamped. When I test for nitrites or ammonia....one or the other is usually present when she gets this way. And, of course, I notice this at the worst possible moment for doing a waterchange (coat on and husband already waiting in the car...) so I find myself frequently having to throw in some Amquel to bind up the nasty stuff till I can do a waterchange. She improves within minutes of adding the Amquel, so I think it is the ammonia that's bugging her.
I've been pondering what makes this tank different, and that's when I had my epiphany. I've been trying to push the pH and hardness of this tank down to see if I could influence the gender ratio of the fry, so it's been getting a good dose of RO during waterchanges. I usually mix 50/50 dechlorinated tap and RO, and if I have enough RO left, this tank gets a little more. In general, I'm not usually successful moving my tap water's pH, so I had assumed it had moved in the direction of 7 but not much past it....like the other tanks were doing. I checked this evening and apparently I've made it well into the low to mid 6's, and I also noticed that the alkalinity is waaaay low, too. (Probably should fix that as well....)
So then I recalled all those times in the past when we've had speakers come and talk about keeping the occasional fish (usually some special fussy dwarf cichlid from the Amazon) in the 4 to 5 pH zone. They've all thrown in the warning that biological filtration gets weird at low pH.......and now I'm kicking myself for not paying more attention. I did a quick google search, and it seems that our usual nitrogen cycle players start to get a bit sluggish around pH 6.5. I wonder if that's what's contributing to my problem. (Slow nitrogen cycle + extra food for the fry = accumulated ammonia).
Has anyone kept fish at low pH, and what did you do to compensate? Did anyone do a better job of listening to our speakers on this topic than me?
Here's the situation: I have a tank rack with 16, 10 and 15 gallon tanks, all filtered with HMFs, and until now, they've been rock solid and seem to handle whatever nastiness comes their way. I have one 10 gal tank (with one pair of Pelvicachromis and a handful of fry) that keeps having both bacterial bloom and issues with a successful nitrogen cycle. I've re-seeded the filter from other tanks, I've given it more frequent waterchanges and I even (gasp) added various bacterial products to it. But still every few days I walk by and see the female Pelvicachromis swimming in one place mid-water, staring straight ahead with fins clamped. When I test for nitrites or ammonia....one or the other is usually present when she gets this way. And, of course, I notice this at the worst possible moment for doing a waterchange (coat on and husband already waiting in the car...) so I find myself frequently having to throw in some Amquel to bind up the nasty stuff till I can do a waterchange. She improves within minutes of adding the Amquel, so I think it is the ammonia that's bugging her.
I've been pondering what makes this tank different, and that's when I had my epiphany. I've been trying to push the pH and hardness of this tank down to see if I could influence the gender ratio of the fry, so it's been getting a good dose of RO during waterchanges. I usually mix 50/50 dechlorinated tap and RO, and if I have enough RO left, this tank gets a little more. In general, I'm not usually successful moving my tap water's pH, so I had assumed it had moved in the direction of 7 but not much past it....like the other tanks were doing. I checked this evening and apparently I've made it well into the low to mid 6's, and I also noticed that the alkalinity is waaaay low, too. (Probably should fix that as well....)
So then I recalled all those times in the past when we've had speakers come and talk about keeping the occasional fish (usually some special fussy dwarf cichlid from the Amazon) in the 4 to 5 pH zone. They've all thrown in the warning that biological filtration gets weird at low pH.......and now I'm kicking myself for not paying more attention. I did a quick google search, and it seems that our usual nitrogen cycle players start to get a bit sluggish around pH 6.5. I wonder if that's what's contributing to my problem. (Slow nitrogen cycle + extra food for the fry = accumulated ammonia).
Has anyone kept fish at low pH, and what did you do to compensate? Did anyone do a better job of listening to our speakers on this topic than me?
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