Is There Such A Thing As Too Much Dechlorinator

[backtotropical]

I've actually been trying to think through why the CO2 fluctuation issue (with Python fillings) would *not* be an issue if one were doing pressurized. Would it be that the CO2 levels were higher to begin with so the tap water coming in would not be causing an "up" fluctuation? I remember that there are CO2 variations day to night in typical pressurized setups but I can't remember how the graph of CO2 across 24 hours would end up looking in a typical well-maintained pressurized setup. (?)

Yes, you're absolutely correct. The CO2 fluctuation isn't so much of a problem in tanks with pressurised CO2 because the CO2 level in the tank is already higher, and the CO2 rich tap water doesn't cause the increase in CO2 levels which would occur in a non-pressurised setup.

However, the level of CO2 isn't the defining factor in triggering algae, but more how stable the level is. So water changes will contribute towards algae blooms in both situations. In a pressurised CO2 setup, the level of CO2 is so high, a water change will drastically reduce the level, detracting from the CO2 stability.

I can only assume that the effect of this isn't so great as the opposite scenario, but again I'm not sure why. Maybe I should move this thread to the planted section.........

I've never trusted the dechlorinating for the whole tank if using a python rule. I use a python for my water changes and mostly double dose my dechlor but only for the amount of water being changed, not the whole tank. I've never ran into any problems with it.

In response to the original question, I think overdosing is fine if you dose 2x, 3x, 4x, 5x the recommended dose (but maybe not during cycling as mentioned above), just don't throw a whole drum of dechlor in the tank because the fish might not like it.

Cheers

BTT (returned from the dead)

 

[waterdrop]

Hi BTT,

There was a single post that I thought satisfactorily helped explain the recommendation to wholedose when doing a Python-technique change. I don't know if I can find the post but I think it was the member who has "mars fishcare" in her avatar (maybe...) I remember thinking at the time it was a pretty good explanation.

And yes, I was trying to make a strong distinction between how you would dose during or not during fishless. The "not going over 2x" thing is definately just a concern (if indeed its correct) during fishless cycling.

~~waterdrop~~

 

[OldMan47]

I must chime in to support WD here. The only empirical research on dechlorinator that I am aware of is Havonec's. That means that we should be treating a double dose as the absolute maximum of any tank. The difference between treating a whole tank, when using a hose, and treating a bucket is quite simple. When you add to a tank, the dechlorinator interacts with organic nitrogen material in the water to neutralize it. In a mature tank, there are tons of natural nitrogen sources that will use up some of the dechlorinator so the recommendation becomes treat the whole volume including the new water. In a bucket situation, the only chlorine present is in the form of the added chlorine, which takes a lot less dechlorinator to handle it. There is almost no organic material in a bucket situation so you need not account for it in your water treatment. The 2x recommendation limit is very real and should not be ignored, it can really affect your beneficial bacteria growth, like it or not.

 

[raptorrex]

I must chime in to support WD here. The only empirical research on dechlorinator that I am aware of is Havonec's. That means that we should be treating a double dose as the absolute maximum of any tank. The difference between treating a whole tank, when using a hose, and treating a bucket is quite simple. When you add to a tank, the dechlorinator interacts with organic nitrogen material in the water to neutralize it. In a mature tank, there are tons of natural nitrogen sources that will use up some of the dechlorinator so the recommendation becomes treat the whole volume including the new water. In a bucket situation, the only chlorine present is in the form of the added chlorine, which takes a lot less dechlorinator to handle it. There is almost no organic material in a bucket situation so you need not account for it in your water treatment. The 2x recommendation limit is very real and should not be ignored, it can really affect your beneficial bacteria growth, like it or not.

that is as i understand the comments made by Havonec. leaving aside that many don't use it at all. BTT, myself and others dose only for the "changed" water. yet, seem, to have no problems.
its not just my own scepticism, either. Amquel, instruct you to,

treat it only for the number of gallons you add, not the entire pond or aquarium volume.

taken from Amquel. but do say

Adding too much de-chlorinator is not detrimental to the fish

. whilst i wont past links, many other makers say the same. mind you, most say you cant overdose, either .

personally i would like to hear more than one maker, backing the whole tank dose, and their explanations. ok, so i ain't looked into all sellers of the stuff.

 

[waterdrop]

BBB/Raptor, your comments are well-taken in that, like many of our bits of know-how, the advice not to overdose beyond 2x hangs simply on a thread from Hovanec and not on info from multiple sources really, that I know of. I suppose I for one tend to hold most of his info in pretty high regard after having read each (well, 3 that I recall and have lying around the house) of his published scientific papers -- its clear when you read them that he has truly done science directly on cycling and that's just better than other things we've got. (Sorry, I realize this doesn't go to the whole tank vs. replaced percentage question.) (I do think OM47's comments go closly toward the one set of good comments I remember about that and I should do more research into finding that Mar's lady's comments...)

We must all remember (and especially make clear to beginners reading here) that the other large complicating factor here is that conditioner dosing is rather a different thing in an immature (6 month old or even a year or less) tank vs. a mature tank. Many if not most of the comments from experienced fishkeepers about hosing in cold tap water and not bothering to warm up or condition it are referring to mature tanks that have well established biofilters. Under a certain percentage change, I'm completely ok with that except to say that conditioner is cheap compared to most tropical fish species and the work that's been put into raising them well! (Tolak has always been good about reminding us of that!) I think many of the beginners will not have seen the large and long discussions of all this over the years unless they really get into searching old stuff.

~~waterdrop~~

 

[raptorrex]

your point is taken. (perhaps we need to make a new thread. but then, it is the subject of this thread). but surly the discussions, and any conclusions, amongst the "more experienced" members. result in a forum consensus (hopefully)

I am not so much worried about the 2x rule. especially as any (listed) toxicity from sodium thiosulphate, does not happen until, over, 5000ppm concentrations. (EEC/US figures). indeed, toxicity, does not worry me at all.

but the comments on "whole" tank dosing. especially as no information, as to its reactions with organic nitrogen, is mentioned. (in any published papers and legislative information) actually. the only info i can find, suggests ST, is good for water bacteria.

I must admit the "whole" tank dosage, does have a wiff of "fishkeepers Snake Oil" about it. to me anyway. even more so as the dosages are made with no reference to the, actual, quantity of chlorine/chloramine the water may have.