A temperature controlled fan system for topical acquarium

[CocaCola]

I always used the simplest method to remove chlorine that I consider as classic. Just leave bucket of water for a day before pouring it to fish tank. Not a problem for mentioned tank volumes.

In the US (and many other countries) municipalities now use chloramines to treat water instead of traditional free chlorine, so the old school practice of airing out for 24 hours no longer works in many places, in fact it has little effect at all on chloramines...  This is the reason treatment plants have switched to chloramines, they are exponentially more stable in water... To properly gas out chloramines you would realistically have to leave that bucket sitting out for several weeks if not a month or longer, depending on if it's indoors or outdoors as the suns UV will assist in removal...  Even boiling is not effective in chloramine removal, the half life of chloramine at a boil in water is in excess of 24 hours, so even after boiling for 72 hours you would still have about 1/8 the chloramine left in that sample, and an exponentially smaller sample of water if any left ...  Activated carbon works but it needs LONG exposure times, catalytic carbon works faster but still needs signification exposure time...

Chemical neutralization/removal with sodium thiosulfate is near instant and very cost effective, IMO it's the only real practical way to remove it in any volume with any speed...

I did a TON of research on this topic a few years back when I decided to get back into my aquarium hobby as I was on municipal water...  In the end I decided I was going to drill my own shallow well in the backyard and use ground water instead of dealing with removal all the time, since I wanted to use a 24/7 drip system to provide a constant water change cycle and chemical removal treatment would complicate that type of system...  But, before that happened we move and I'm now on untreated well water, but still have not got around to setting up my aquariums as the move has disrupted everything...

[Vineyards]

Let's clarify something, if you use thiosulphate for chlorine removal what you are saying is right. However, if you mean we can remove chloramines by adding thiosulphate you are wrong. The only quick way to get rid of chloramines is by chlorine shocking. It works like this, if you have 0.4ppm of chloramines (i.e. monochloramine, dichloramine, trichloramine) you should shock ten times as much chlorine i.e. 4 ppm.
Since this will kill all of your fish instantly, you should do this outside the fish tank and remove chlorine with either thiosulphate or by carbon filter. After making sure that you don't have either chlorine or chloramines. Of course this is not a very practical solution and much more expensive than RO water. But getting a RO unit may not be easy either. In either case, you should analyze your water to learn the concentrations of the aforementioned.

By the way, thiosulphate is a bit expensive, metabisulphite could do the same job more cheaply I suppose.

[CocaCola]

However, if you mean we can remove chloramines by adding thiosulphate you are wrong.

I fully beg to differ on me being incorrect, there are two reactions happening...

In incomplete generic terms, sodium thiosulphate first breaks down the chloramines into their respective chlorine and ammonia components then proceeds to remove the chlorine component leaving behind the ammonia component, this is why it's advised to use twice as much sodium thiosulphate to remove chloramines vs free chlorine as it's a two stage reaction and requires more sodium thiosuphate to complete to job...  The residual ammonia will generally be removed quickly by a proper functioning bio filter in a tank, or another remover can be used if there is a concern, this is why a product like Prime is nice as it has the extra ammonia reducer...

Reaction one against chloramine:

Na2S2O3 + 4NH2Cl + 5H2O = 2NaHSO4 + 4NH3 + 4HCl

Na2S2O3 (sodium thiosulphate) + 4NH2Cl (chloramine) + 5H2O (water) >---yields---> 2NaHSO4 (sodium bisulfate) + 4NH3 (ammonia) + 4HCl (hydrogen chloride)

Reaction two against the chlorine:

10Na2S2O3 + 20HCl = 20NaCl + 15SO2 + 5S + H20

10Na2S2O3 (sodium thiosulphate) + 20HCl (hydrogen chloride) >---yields---> 20NaCl (sodium chloride) + 15SO2 (sulfur dioxide) + 5S (sulfur) + H20 (water)

Either way be it chloramine or chlorine it's neutralized by the sodium thiosulphate in the end...

By the way, thiosulphate is a bit expensive

Expensive? It's 10lbs delivered to my door on Ebay for $23 that is enough to treat 45,000+ gallons of water at recommend two times chloramine removal rates or about 90,000+ gallons of water at free chlorine removal rates...  With testing of your water source those numbers can be further adjusted as to not waste, they error on the side of caution...

In a more real world perspective that $23 purchase of 10lbs will allow you to process almost 500 gallons a week for 2 years, or about $12 a year for weekly 500 gallon water changes...  That is chump change in the grand scope of what it cost to maintain an aquarium...

** Edit the site bellow suggest 10lbs of sodium throsulphate will actually treat up to 1,535,699 gallons, so my math might very well be off in the above, might have missed a 10 factor or something in my quick off the top of the head math...  Either way if this site is correct that pushes the cost to well bellow what I estimated above, as that 10 pounds should now last you 59 years with 500 gallon a week changes, equaling a yearly cost of 40 cents!

http://www.jonahsaquarium.com/JonahSite/dechlor.htm

I just looked at Ebay prices for sodium metabisulphite, it's 10 cents cheaper for 10lbs vs thiosulphate, so price wise it's a wash...

[pickit2]

using sodium metabisulphite, you could also take up brewin' beer to offset the cost.

[Vineyards]

OK. CocaCola:) Frankly, I didn't know about the reaction sequence of thiosulphate and chloramines. That information is useful to me too.

A couple of years ago, I tried to remove chloramines in an experiment using metabisulphite which seemed to fail. In the case of fish tank, it is probably a no-gain situation as ammonia is still the worst enemy for the fish and its presence is probably worse than that of chloramines.

As for the price difference, where I live sodium metabisulphite is abundantly found in all grades. You know lab grade is greatly more expensive and that is the case with thiosulphate. I find lab grade one through my connections. That might explain the price difference. Since I consume larger amounts (for non-fish tank applications) I remembered the price issue. As you say a 10c difference per kilo is nothing.

As a result, if we keep this to fish tanks specifically since we can resort to biological removal methods it may be ok to use thiosulphate but for my applications it has no use since one ends up with ammonia which is even worse than chloramines. It is like rewinding chlorine (disinfection) reaction.



Posted on: January 08, 2015, 01:16:31 01:16 - Automerged

using sodium metabisulphite, you could also take up brewin' beer to offset the cost.

They use this substance for countless things. Are you brewing your own beer? I know it is one of the oldest drinks. It musn't be extremely difficult to make beer. Still the Scots have a better use for malt: Scotch whisky.

[CocaCola]

In the case of fish tank, it is probably a no-gain situation as ammonia is still the worst enemy for the fish and its presence is probably worse than that of chloramines.

If you source water has 4 PPM chlorine (as chloramine, the maximum allowed in the US) and use sodium thiosulphate to neutralize it, the end result is 4 * (17/51.5) or 1.32 PPM ammonia...  Now yes that is high in itself , but now consider you are only doing say a 20% water change, all the sudden you are down to 0.26 PPM in the tank, and in a properly cycled tank the bio filter should knock that down in short, if you have plants or a carbon filter in there even faster...  And that is the maximum allowed in the US, very few places have anywhere near that high of a level at the tap...

I just looked up the water report from chloramine levels where I used to live, and they show the min at .03 PPM and the max at .08 PPM as tested at random residential faucets last year...  So doing the worst case at that old house 0.08 * (17/51.5) equals about 0.026 PPM ammonia, even doing a 50% water change that is only 0.013 PPM ammonia, mostly unmeasurable using home testing kits and that low of amount will be taken out of the water in very short with a proper bio filter...

Either way that is why I said using a commercial product like SeaChem Prime that has ammonia binders in it is convenient for the hobbyist...

using sodium metabisulphite, you could also take up brewin' beer to offset the cost.

Yeah, a lot of brewers use Campden tablets (metabisulphite) because it 'taste' better and they have them on hand anyway to kill bacteria and bad yeast, thiosulphate is pretty much the standard in the pond/aquarium realm...  I don't do beer, but I do make that two process clear stuff that is sorta similar and for that I always use boiled well water, RO water or sometimes boiled rain water depending on my mood...

[Vineyards]

If you source water has 4 PPM chlorine (as chloramine, the maximum allowed in the US) and use sodium thiosulphate to neutralize it, the end result is 4 * (17/51.5) or 1.32 PPM ammonia...  Now yes that is high in itself , but now consider you are only doing say a 20% water change, all the sudden you are down to 0.26 PPM in the tank, and in a properly cycled tank the bio filter should knock that down in short, if you have plants or a carbon filter in there even faster...  And that is the maximum allowed in the US, very few places have anywhere near that high of a level at the tap...

I just looked up the water report from chloramine levels where I used to live, and they show the min at .03 PPM and the max at .08 PPM as tested at random residential faucets last year...  So doing the worst case at that old house 0.08 * (17/51.5) equals about 0.026 PPM ammonia, even doing a 50% water change that is only 0.013 PPM ammonia, mostly unmeasurable

We say chloramines in general but the kind of chloramine used in potable water disinfection is monochloramine, (di and tri are the subsequent steps and are not to be found in water at all). As a result, we should also limit this to monochloramines. Did water contain 4 ppm trichloramine for example, you wouldn't be able to drink that water. Its smell would put you off and it would be toxic. This should not pose a problem for a fish tank as long as make up water contains very small amounts of chlorine. 

[PeterMcMonty]

Hello,

I made two temperature sensors encapsulated in glass vial caps, filled with thermal conductive silicon grease and sealed with silicone sealant, as described here in my first post.

The first one (see photos attached to my first post) was made around dec 26th, 2014 and since then has been dipped in my acquarium and connected to the temperature controller.

The second one (see photo attached here) was made around jan 10th, 2015 and since then has been dipped in water and connected to a second unit of my temperature controller.

Both of them remains perfectly sealed after almost three months and I'm convinced that this implementation technique is the most convenient one.

In particular:
- SMD components are more practical than PTH ones that I used in my previous probes;
- a small double sided PCB, drilled for LM35 and milled with a minidirll cutting tool, makes a very good support for the probe components, small enough to fit in the vial cap (I used 1,6mm laminate because I don't have 0,8mm laminate, but this last would be even better);
- silicone sealant makes a very good seal both with glass and wires silicon coating, preventing water to get in by capillarity;
- thermal silicon grease makes a very good thermal contact between glass and LM35 case, giving a very fast thermal response to the probe; in particular, I've been able to appreciate within few seconds the temperature differences between various parts of my acquarium: for example, bottom water is about 0,3°C colder than water at 10 cm from bottom.

As silicon insulated wire I used some 28 AWG (ext. diameter approx. 1.8mm) that was available in my previous working place. Now I don't have much more of this, but I made a small research on RS components Italy and I found some wire suitable for this application, made by two german producers:

Cavo di collegamento apparecchiature 0,25 mm², trefoli 130/0,05 mm, 300/500 V
Hew Heinz Eilentropp cod. 8955-xx-yyy
              coil   5m          RS €4,28         coil   20m        RS €16,37       coil   100m      RS €67,42  RS €68,10
black      8955-01-005  2222-4107      8955-01-020  2222-4113      8955-01-100                    2222-4129
red         8955-03-005  2222-4135      8955-03-020  2222-4141      8955-03-100  2222-4157
yellow    8955-05-005  2222-4236      8955-05-020  2222-4258      8955-05-100  2222-4264
green     8955-06-005  not available   8955-06-020  not available   8955-06-100  2222-4220
blue       8955-07-005  2222-4163      8955-07-020  2222-4179      8955-07-100  2222-4191
http://it.rs-online.com/web/c/cavi/cavi-fili-unipolari/cavi-collegamento-per-apparecchiature/?searchTerm=cavo+isolamento+silicone&sort-by=P_breakPrice1&sort-order=asc&applied-dimensions=4294026774&esid=cl_4294967294,cl_4294684510,cl_4294684693,cl_4294026795&m=1

Cavo alta temperatura Unipolare Lapp, 300 V, Ø esterno 0.0019m, in rame e silicone, non schermato
Lapp cod. 47x0y
              coil   100m  RS €22,77
black         47001      724-4443
blue          47002      724-4446
brown       47003      724-4440
yellow       47005      724-4459
red            47104      724-4452
white        47105      724-4456
grey          47106      724-4465
http://it.rs-online.com/web/c/cavi/cavi-fili-unipolari/cavi-per-impieghi-pesanti/?searchTerm=cavo+isolamento+silicone&applied-dimensions=4294026774&esid=cl_4294967294,cl_4294026795&m=1

The Hew Heinz Eilentropp cod. 8955-xx-yyy is convenient if you need small quantities in different colours (5m coils), while the Lapp cod. 47x0y is the cheapest in 100m coils (one colour).

I guess that the same articles are available on RS international, as well as as similar wires may be available by others international distributors (Farnell, Digi-Key, Mouser, etc.).

Silicon is a very good insulator that stands higher temperatures than PVC and doesn't releases any chemicals in the acquarium (PVC or other insulating plastics may do). moreover, PVC (and worst Teflon) doesn't seal with silicon sealant as well.

NOTE: allow silicon sealant to dry perfectly (at least 48 hours) before dip it into acquarium water.

So, enjoy yourself with this project and your acquariums.
PeterMcMonty

[PeterMcMonty]

@kcwcc

Thank you for your appreciation!

Answers to your inputs:
1. I'm italian: Italy is the land of wine (yes... France too... but we have the best ones ). But I don't like wine so much... I ADORE beer!!! Here we have quite good beer brewers in north east (region of Friuli Venezia Giulia and around): they are close to Austria and Slovenia, so they brew a quite good Pils.
But my preferred are british Bitter and irish Extra Stout (yes, industrial Guinness too!). I drink german Lager, but I don't think is more than ordinary. I hate belgian and some french beers because they taste too sweet. Curiosity abut Guinness: they do market researches to adapt their product taste to what they guess is the best for each country... the result is that the (apparently) same pint of Guinness you drink in a Dublin's pub is tastes different to that drunk in London and QUITE different to what I can drink here in Italy and furthermore it has changed taste seveal times in the past forty years!!! Some years ago italian Guinness tasted SWEET (BLEAH!!!), but luckily now the taste is a bit closer to irish original (I said closer, NOT the same ). About Bitter, well, this is almost unknown here at the edge of the beerland, but sometimes I've been lucky and I found it... I can't afford a trip to London every time I want a good pint of bitter!
So, as far as beer is concerned, I'm an user, not a maker, but I appreciate so much what you do!

2. Thank you for your hint! I was not aware about Maxim's DS18B20 (http://datasheets.maximintegrated.com/en/ds/DS18B20.pdf) nor that it is available online already sealed and waterproof, as in this example:
http://www.lightinthebox.com/it/ds18b20-sonda-di-temperatura-digitale-impermeabile-nero-argento_p2429526.html?currency=EUR&litb_from=paid_adwords_shopping&gclid=CKDQqdP05MQCFQjKtAodfE0ACQ
The output is 1 wire digital 9 to 12 bit programmable, with a resolution of 0.0625°C (12 bit), the conversion speed is not so fast ( 750 ms at 12 bit), but temperature is a very slow varying phisical parameter in a water tank, so this is not a drawback. Effectively, In my system I perform an average of 12,500 readings summed toghether to get one average read and it takes about 700 to 750 ms.
Another advantage is that It's possible to control many devices on the same 1 bit bus, by paralleling them, so getting a network of measuring points.
Effectively, it is a quite interesting device and maybe I'll use it in my next design. Thanks again!

3. For sure heat exchange, as done in refrigerators and air conditioners, is much powerful and works well in any condition. It saves water that has not to be refilled continously with RO water and lets you keep temperature at 25°C constantly with no compromises. But it is also more complicated to implement. I live in an apartement at 7th floor, so I don't have a well with water at 14°C and my wife would not be happy with a bunch of plasting tubing in the refrigerator with some twenty meters of it running from the kitchen to the living room where the acquariums stay. Of course we have no air conditioners because both of us had got bad experiences with near-pole-keeped of such devices, expecially in some countries like China (Hong Kong in particular), Near East and North Africa... not excluded here in Italy in some public offices or banks: When you came from a confortable 40°C dry climate and enter into a 15°C chilled air conditioned public office and viceversa... well a bad disease will expect you soon!
So, I preferred a softer approach: that of fan system. It is simpler, ecological (no heat pollution for the ambient, less energy consumption) and softer. It has its limits: if it is very hot and very wet (humidity more than... say 95% ? ... well, it is almost impossible to pretend that more water evaporates in an already saturated air. But this happens two or three days a year and it's not a big issue.

By the way, I saw some heat exchangers for acqarium, see for example: http://en.tecoonline.eu/ (an italian firm, not far from where I'm living), but they are not so common and they cost a lot of money (some 400 to 500 € if I remember....). Not for me.

Hope to meet you next and drink a chilled beer togheter, dear pal!