That's great, Darwin! A little worrisome that you show no nitrites, but since your tank had been cycled before, probably not unusual.
Hope all continues to go well
Roan
Hope all continues to go well
Roan
Help ! cloudy water - what do i do ???
- Thread starter Darwin
- Start date
I hate to be contradictory after 2 pages of advise and plenty of corrections, but there's nothing wrong with a KH of 2 degrees, unless you're injecting CO2. It simply means that you can't be slack on water changes. Our tap KH is often lower, sub-1 degree (roughly 10 ppm) and my pH is rock solid.
Shoot to do a 50% change weekly, minimum (which could be 2 30% changes or 3 20% changes, whichever regime is most convenient). Consider that a 5 gal bucket will give you a 25% change in about 10 minutes. I've actually started doing daily changes on my 18 gal tank after work. It's dead easy and takes no time, and I've never seen the colour and activity that my fish are showing. Anecdote aside, leave the crushed coral in the filter, it won't hurt anything (dissolution is slow) and will be a good failsafe, but stop adding bicarbonate.
The amount of salt that you were adding was negligible. It's the "tonic" amount recomended by lfs salespeople (not to be confused with enlightened aquarists working at lfs') because it won't do any harm (nor any help).
The pH-Down is the most likely culprit for your crash. Always be very wary of making any pH mods, consider a strong acid titration of a weakly-(or non-)buffered solution, remember what happens to pH at the end-point? (it takes a rapid dive for the non-chemists) pH - KH in effect - is not something to be monkeyed with by the faint of heart. Any modifications have to be made very carefully and consistently, and only for very special reasons - like wild caught specimens or breeding.
Finally, what's the colour and turbidity of a saturated ammonia solution? Crystal clear, but it will kill pretty much anything in it.
Clarity is not an indicator of water quality. In the event of a bloom such as that the best course of action is to aerate (something I seldom advocate) or lower the water level so that the filter splashes. The shearing force between filter return and water surface is excellent for gas exchange. Your only real concern during a bloom as severe as you described is O2 content. With that high a bacterial density the O2 demand spikes. If I had to guess, I'd say that the pH-Down killed or seriously distrupted your free floating fauna resulting in the bloom and the resulting O2 depletion killed your nitrifying colonies.
Shoot to do a 50% change weekly, minimum (which could be 2 30% changes or 3 20% changes, whichever regime is most convenient). Consider that a 5 gal bucket will give you a 25% change in about 10 minutes. I've actually started doing daily changes on my 18 gal tank after work. It's dead easy and takes no time, and I've never seen the colour and activity that my fish are showing. Anecdote aside, leave the crushed coral in the filter, it won't hurt anything (dissolution is slow) and will be a good failsafe, but stop adding bicarbonate.
The amount of salt that you were adding was negligible. It's the "tonic" amount recomended by lfs salespeople (not to be confused with enlightened aquarists working at lfs') because it won't do any harm (nor any help).
The pH-Down is the most likely culprit for your crash. Always be very wary of making any pH mods, consider a strong acid titration of a weakly-(or non-)buffered solution, remember what happens to pH at the end-point? (it takes a rapid dive for the non-chemists) pH - KH in effect - is not something to be monkeyed with by the faint of heart. Any modifications have to be made very carefully and consistently, and only for very special reasons - like wild caught specimens or breeding.
Finally, what's the colour and turbidity of a saturated ammonia solution? Crystal clear, but it will kill pretty much anything in it.
Clarity is not an indicator of water quality. In the event of a bloom such as that the best course of action is to aerate (something I seldom advocate) or lower the water level so that the filter splashes. The shearing force between filter return and water surface is excellent for gas exchange. Your only real concern during a bloom as severe as you described is O2 content. With that high a bacterial density the O2 demand spikes. If I had to guess, I'd say that the pH-Down killed or seriously distrupted your free floating fauna resulting in the bloom and the resulting O2 depletion killed your nitrifying colonies.
Ah! But happychem, I disagree!happychem said:
In a cycled tank, yes, a KH of 2 is more than fine. I have several tanks with a KH of 2. What I have found, however, is that when I am cycling a tank with a KH that low, I will crash if I do not either water change or add baking soda beforehand. It's happened to me a couple of times now.
Maybe because of an "accelerated" cycle -- like when you use Bio Spira, filter media, or are "recycling" for whatever reason. Is it not possible that, given that many of the needed bacteria are already present and there is an abundance of "food" and space, that they mulitply more rapidly than normal? Thus depleting the bicarbonate at a much faster rate than normal?
Not possible? Yes? No? Yer off yer rocker?
Something has to account for the pH crashes I've had while cycling with Bio Spira with a 2 dKH. It hits 0 in 1-2 days if I don't buffer.
This was the premise I was basing my advice on in helping Darwin. Any enlightenment would help, please
Darwin,
I don't think happychem is saying that the advice I gave you to help you recover was bad, but rather my reasoning and cause/effect are faulty. Hope he clarifies!
Roan
Roan, the rate of buffer depletion is dependant on the rate of H+ production by the nitrifying colonies, which, in a cycled tank, is controlled by the rate of NH3 production.
In other words, if there are no established bacteria or no ammonia source, the buffer shouldn't deplete. In the case of an "accellerated" cycle you are effectively bringing the nitrifying colony from 0 to plenty, but the kinetic effect remains dependant on the ammonia source. In other words, if BioSpira were added and the fish were added the next day, or 12 hours later, then there should be no difference from a completed cycle in terms of H+ production and buffer consumption.
However, if the fish were in the tank for a few days producing ammonia prior to bacterial innoculation, then the abundance of food could result in a short lived pulse of H+ decreasing the buffer. However, this would not be indicative of a need for buffer addition in the cycled tank where bacterial H+ production is limited by NH3 production, which in general is not sufficiently fast to burn through the 35 ppm of buffer (a rough estimate of 2 degrees) in a week - assuming a proper stocking level.
Also, water utilities often buffer their treated water with polyphosphates to prevent corrosion in the lines and improve Cl2 life span. However, these would be consumed by plants and algae in the aquarium as a source of P. The result would be a baffling decrease in KH, because, of course, the aquarist assumes only carbonaceous species.
To come to the point, no, Roan, your advise was not wrong, per se. I was just trying to keep her life as simple as possible - the initial problem being too much monkeying with water chemistry.
The bottom line is that if your pH is crashing during your cycle, or during the week, and you are keeping up a proper weekly maintenance and not overstocking, then a little baking soda is the way to go.
As always, start from the advise here (which is usually fairly general) and modify to suit your settings. Otherwise you're not really learning aquatic husbandry, you're just following directions.
In other words, if there are no established bacteria or no ammonia source, the buffer shouldn't deplete. In the case of an "accellerated" cycle you are effectively bringing the nitrifying colony from 0 to plenty, but the kinetic effect remains dependant on the ammonia source. In other words, if BioSpira were added and the fish were added the next day, or 12 hours later, then there should be no difference from a completed cycle in terms of H+ production and buffer consumption.
However, if the fish were in the tank for a few days producing ammonia prior to bacterial innoculation, then the abundance of food could result in a short lived pulse of H+ decreasing the buffer. However, this would not be indicative of a need for buffer addition in the cycled tank where bacterial H+ production is limited by NH3 production, which in general is not sufficiently fast to burn through the 35 ppm of buffer (a rough estimate of 2 degrees) in a week - assuming a proper stocking level.
Also, water utilities often buffer their treated water with polyphosphates to prevent corrosion in the lines and improve Cl2 life span. However, these would be consumed by plants and algae in the aquarium as a source of P. The result would be a baffling decrease in KH, because, of course, the aquarist assumes only carbonaceous species.
To come to the point, no, Roan, your advise was not wrong, per se. I was just trying to keep her life as simple as possible - the initial problem being too much monkeying with water chemistry.
The bottom line is that if your pH is crashing during your cycle, or during the week, and you are keeping up a proper weekly maintenance and not overstocking, then a little baking soda is the way to go.
As always, start from the advise here (which is usually fairly general) and modify to suit your settings. Otherwise you're not really learning aquatic husbandry, you're just following directions.
Thanks for the follow up - I had been wondering about the consumption of carbonate. To begin with I thought it was only due to H+ produced during the nitrogen cycle but then I got the impression that it was due to actual consumption of carbonate by the bacteria (possibly a misunderstanding). That also got me wondering about whether some plants use carbonates as a carbon source.
Just wondering what are the free floating fauna in the tank ?
When it happened I thought it might have been because the clown died. I found him in the morning and he looked like he'd been dead for awhile and the water was only slightly cloudy at that point. Perhaps if he was already decomposing that could have caused a bloom. When time I got home and the water was white the danios were gasping at the surface, so O2 depletion was probably the problem there. Otherwise, at the time i was doing very frequent water changes because of the sick clown.
I don't quite understand this bit. Is it that polyphosphates can be an important source of buffering in tap water and that if these are depleted by plants, than you end up relying more on KH for buffering and might see more pronounced decreases in KH. In this case I would think that it be good to have a bit more carbonate buffering capacity. Or am I missing the point entirely ????
happychem said:
Just wondering what are the free floating fauna in the tank ?
When it happened I thought it might have been because the clown died. I found him in the morning and he looked like he'd been dead for awhile and the water was only slightly cloudy at that point. Perhaps if he was already decomposing that could have caused a bloom. When time I got home and the water was white the danios were gasping at the surface, so O2 depletion was probably the problem there. Otherwise, at the time i was doing very frequent water changes because of the sick clown.
happychem said:
I don't quite understand this bit. Is it that polyphosphates can be an important source of buffering in tap water and that if these are depleted by plants, than you end up relying more on KH for buffering and might see more pronounced decreases in KH. In this case I would think that it be good to have a bit more carbonate buffering capacity. Or am I missing the point entirely ????
What if the water contains 1.0 ppm NH4+? Along with regular stocking, of course, and added all at the same time at the very beginning with Bio Spira. Would that be sufficient to cause KH depletion?happychem said:
Good point, and yes, mine is buffered with phosphates. However, and this is exactly what you are saying is wrong -- I WAS under the impression that plants consumed organic phosphates and not inorganic. At least, that's what I thought RTR was saying in a different thread. So, either I misunderstood RTR or I'm totally out in left field.
Can you explain further?
Noted
Roan
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Ooof! I'll try, but to be fair, I just moved and have been incommunicado for a while, so my head's really not in the game right now.
Darwin, certainly the dead loach could have caused the bloom, I was just guessing at a timeline, but if the water was already cloudy it points to an existing disequilibrium in the free floating fauna. This is fairly common in newly established aquaria since you're starting from scratch, so everybody has to learn their place, if you catch my drift. Any perturbation during this initial equilibration time is going to prolong the bloom, evidently, it got much worse in this case.
You're not missing the point entirely, you're skirting it. The confusion here, I think, stems from the term KH, or carbonate hardness. Namely because that isn't what's being measured. What we're actually measuring is Alkalinity, the sum of all strong bases less the strong acid concentration. I've written an exhaustive description in the "Water Chemistry" article which can be found in "Article Corner". As a chemist, you might even understand some of it!
Basically, both polyphosphates and carbonate species act as buffers. When you measure KH, you measure both; however, polyphosphates are consumed as a phosphorus source.
Yes, most plants and algae (at least marine algae), are capable of decarboxylation - using carbonate as a carbon source. However, the enzyme used to reduce the carbonate (Rubisco) is the slowest enzyme in the world, so this is not a favoured pathway for carbon uptake. Plants improve on this somewhat by saturating the enzyme with CO3, but it's still a slow process.
Plant uptake of CO2 is another possible route of carbonate removal, again, slow and I'm not convinced of its significance beyond theory. In theory when plants take up CO2 during the day, carbonate equilibrium will shift to replace the lost CO2. In theory this would increase pH and have no immediate effect on KH (because of the concommitant decrease in [H+]). However, the net result will be a decrease in [CO3--] and [HCO3-], leaving the system more vulnerable to H+ addition by bioacidification.
Roan, PO4 and polyphosphates are inorganic phosphate, this is analogus to CO2 being inorganic carbon. An example of organic phosphate might be a phospholipid or other compounds in which phosphorus was associated with carbon and hydrogen. As for whether plants will use organic PO4, I don't know. Probably they can, but there isn't a whole lot of it floating freely and using that which is built into their tissue would probably be a last resort.
Darwin, certainly the dead loach could have caused the bloom, I was just guessing at a timeline, but if the water was already cloudy it points to an existing disequilibrium in the free floating fauna. This is fairly common in newly established aquaria since you're starting from scratch, so everybody has to learn their place, if you catch my drift. Any perturbation during this initial equilibration time is going to prolong the bloom, evidently, it got much worse in this case.
You're not missing the point entirely, you're skirting it. The confusion here, I think, stems from the term KH, or carbonate hardness. Namely because that isn't what's being measured. What we're actually measuring is Alkalinity, the sum of all strong bases less the strong acid concentration. I've written an exhaustive description in the "Water Chemistry" article which can be found in "Article Corner". As a chemist, you might even understand some of it!
Basically, both polyphosphates and carbonate species act as buffers. When you measure KH, you measure both; however, polyphosphates are consumed as a phosphorus source.Yes, most plants and algae (at least marine algae), are capable of decarboxylation - using carbonate as a carbon source. However, the enzyme used to reduce the carbonate (Rubisco) is the slowest enzyme in the world, so this is not a favoured pathway for carbon uptake. Plants improve on this somewhat by saturating the enzyme with CO3, but it's still a slow process.
Plant uptake of CO2 is another possible route of carbonate removal, again, slow and I'm not convinced of its significance beyond theory. In theory when plants take up CO2 during the day, carbonate equilibrium will shift to replace the lost CO2. In theory this would increase pH and have no immediate effect on KH (because of the concommitant decrease in [H+]). However, the net result will be a decrease in [CO3--] and [HCO3-], leaving the system more vulnerable to H+ addition by bioacidification.
Roan, PO4 and polyphosphates are inorganic phosphate, this is analogus to CO2 being inorganic carbon. An example of organic phosphate might be a phospholipid or other compounds in which phosphorus was associated with carbon and hydrogen. As for whether plants will use organic PO4, I don't know. Probably they can, but there isn't a whole lot of it floating freely and using that which is built into their tissue would probably be a last resort.
happychem said:You're not missing the point entirely, you're skirting it. The confusion here, I think, stems from the term KH, or carbonate hardness. Namely because that isn't what's being measured. What we're actually measuring is Alkalinity, the sum of all strong bases less the strong acid concentration. I've written an exhaustive description in the "Water Chemistry" article which can be found in "Article Corner". As a chemist, you might even understand some of it!
I found your water chemistry article after my last post, it was a good chemistry refresher, thanks. Clearly I have been taking the 'carbonate' test way too literally ! From what I gather it seems fairly uncommon that people have tap water like mine, which is high pH (8 - 8.2) and low KH (2) and GH (2-3) or according to the water suppliers figures pH 7.8 - 8.7, KH 42 ppm and GH 47 ppm.
