tap water conditioner dosages

[newguy]

Are there any adverse effects associated with using more than the recommended dosage of tap water conditioner?

[Lady Hobbs]

No. You can not over -dechlorinate. I add enough for the whole tank when I do my water changes because I do large water changes. Others only add enough dechlorinator to replace the water they removed. Either way is fine.

[xoolooxunny]

i do either or, depends on if the mood strikes me. but if I'm only replacing 5 gallons in my 75g from a quick vacuum or something, i don't bother with it.

[GoldLenny]

My understanding is that the dechlor product stays in the water column waiting for a new chlorine/chloramine molecule so if you ever have to top off, you should also be OK without re-dosing. I don't like the idea of adding a full dose each time, even when only doing a PWC (partial water change) as eventually, it seems the water would be heavily dosed with dechlor product.

Most dechlor products use various sodium/salt compounds and we know that salt does not evaporate with the water so it could lead to a higher salinity level over time.

Here is the MSDS information on my dechlor.. API Tap Water Conditioner:

sodium thiosulfate_____7772-98-7___30.2%
EDTA tetrasodium salt__64-02-8______9.8%

[newguy]

Thanks for posting the MSDS. I am also using API tap water conditioner. The instructions on my bottle give two different dosages, one for dechlorinating and another for breaking the chloramine bond. There is a 4-fold difference between the dosages, and since I wasn't sure if my tap water contains chloramine, I've been using the higher dosage. I just recently found out that my tap water doesn't have chloramine, so I guess I have been using more conditioner than necessary.

[gm72]

Goldlenny, excellent information. You obviously have a chemistry background/knowledge base. Very good and appreciated!

[Chrona]

It doesn't evaporate over time, true, but you remove it with each partial water change so the maximum possible concentration (given 50% water change) is only 2x what you dose each time. Overdosing by 2x or even 3x is just fine. You don't really need to go past 3-4 dose in most cases so it's moot. People using Seachem Prime (like me) often dose higher than the recommended amount because it's also used to neutralize nitrites/ammonia, etc, in emergencies, and the dosage only removes a certain amount each time.

Not sure what they mean by the 30% concentration, but even a saturated salt (NaCl) solution of 7.5 mL (the dosage for API, one of the least concentrated water conditioners around) placed into a 10g tank would do nothing to the salinity. Heck, even 7.5mL (1.5 tsp) of solid NaCl wouldn't do anything in a 10g. The tonic levels of salt recommended for treating ick and nitrite poisoning falls along the lines of 1 tablespoon per 5 gallons, or 6 teaspoons per 10g.

We'll just say that the stuff is solid NaCl for the purpose of the argument and that you do 50% water changes. Even if you dosed twice the normal dosage of API conditioner each time, your sodium levels would build up to a maximum concentration of 6 teaspoons per 10g, the same as the tonic levels. Though I don't advocate using salt for anything other than treating ick or dealing with nitrite, there are no long term effects from it in such low concentrations. Obviously if you dump that much salt right into the tank, the fish will go into shock from the change in total dissolved solids throwing their osmoregulation way off kilter, but the buildup of sodium from Aquasafe would occur over a very long time.

Long story short, water conditioners can't really be overdosed (within reason - there's no real point to continually dosing more than 2-3x the normal dosage each time)

[Drumachine09]

It doesn't evaporate over time, true, but you remove it with each partial water change so the maximum possible concentration (given 50% water change) is only 2x what you dose each time. Overdosing by 2x or even 3x is just fine. You don't really need to go past 3-4 dose in most cases so it's moot. People using Seachem Prime (like me) often dose higher than the recommended amount because it's also used to neutralize nitrites/ammonia, etc, in emergencies, and the dosage only removes a certain amount each time.

Not sure what they mean by the 30% concentration, but even a saturated salt (NaCl) solution of 7.5 mL (the dosage for API, one of the least concentrated water conditioners around) placed into a 10g tank would do nothing to the salinity. Heck, even 7.5mL (1.5 tsp) of solid NaCl wouldn't do anything in a 10g. The tonic levels of salt recommended for treating ick and nitrite poisoning falls along the lines of 1 tablespoon per 5 gallons, or 6 teaspoons per 10g.

We'll just say that the stuff is solid NaCl for the purpose of the argument and that you do 50% water changes. Even if you dosed twice the normal dosage of API conditioner each time, your sodium levels would build up to a maximum concentration of 6 teaspoons per 10g, the same as the tonic levels. Though I don't advocate using salt for anything other than treating ick or dealing with nitrite, there are no long term effects from it in such low concentrations. Obviously if you dump that much salt right into the tank, the fish will go into shock from the change in total dissolved solids throwing their osmoregulation way off kilter, but the buildup of sodium from Aquasafe would occur over a very long time.

Long story short, water conditioners can't really be overdosed (within reason - there's no real point to continually dosing more than 2-3x the normal dosage each time)


A[Only Registered Users Can See Links.] you beat me to it.

[GoldLenny]

It doesn't evaporate over time, true, but you remove it with each partial water change so the maximum possible concentration (given 50% water change) is only 2x what you dose each time. Overdosing by 2x or even 3x is just fine. You don't really need to go past 3-4 dose in most cases so it's moot. People using Seachem Prime (like me) often dose higher than the recommended amount because it's also used to neutralize nitrites/ammonia, etc, in emergencies, and the dosage only removes a certain amount each time.

Not sure what they mean by the 30% concentration, but even a saturated salt (NaCl) solution of 7.5 mL (the dosage for API, one of the least concentrated water conditioners around) placed into a 10g tank would do nothing to the salinity. Heck, even 7.5mL (1.5 tsp) of solid NaCl wouldn't do anything in a 10g. The tonic levels of salt recommended for treating ick and nitrite poisoning falls along the lines of 1 tablespoon per 5 gallons, or 6 teaspoons per 10g.

We'll just say that the stuff is solid NaCl for the purpose of the argument and that you do 50% water changes. Even if you dosed twice the normal dosage of API conditioner each time, your sodium levels would build up to a maximum concentration of 6 teaspoons per 10g, the same as the tonic levels. Though I don't advocate using salt for anything other than treating ick or dealing with nitrite, there are no long term effects from it in such low concentrations. Obviously if you dump that much salt right into the tank, the fish will go into shock from the change in total dissolved solids throwing their osmoregulation way off kilter, but the buildup of sodium from Aquasafe would occur over a very long time.

Long story short, water conditioners can't really be overdosed (within reason - there's no real point to continually dosing more than 2-3x the normal dosage each time)

Well, I'm glad you don't mind supporting the dechlor companies but I'd rather keep my hard earned money in my own pocket.

If you ONLY put a full and proper dose of dechlor in your tank when you first start it up. For example purposes, lets say the dechlor solution is 1ppm (I know that is high but it's a simple number for example purposes of this reply). Then do a 50% PWC, you would remove 50% of the dechlor also. Then you add another full dose of dechlor instead of a 50% dose when you add the removed 50% of water. This now increased your dechlor solution by 50% or up to 1.5ppm. Then your next 50% PWC, you would remove .75ppm but add 1ppm with the redose so now your dechlor is up to 1.75ppm. Then your next 50% PWC, you would remove .875ppm but add 1ppm so now you're up to 1.875ppm. Over the course of a year, you will be up to 5ppm and then 10ppm, etc.

At what level are you happy with? Do you think your fish can eventually live in 50% dechlor? I don't!

There is no reason to have to rely on overdosing dechlor to control ammonia/nitrites. These are things that should be handled by regular PWC's and proper stocking of a tank. Sure the dechlor companies tell you to do that so they can sell more product but it's just another chemical they are trying to sell to solve the minor issues that should be solved by providing frequent PWC's, filter maintenance and proper ecology in a tank.

Certainly, for folks with chlorine/chloramine treated tap/source water, it is a necessary chemical, unless they want to age the water long enough to allow the chlorine/chloramine to outgas (4days/20days) but I don't mind using this relatively safe chemical at the minimum safe dosage in order to be able to do regular PWC's on my tanks without having buckets and buckets of aging water sitting around for weeks on end (I have chloramines in my water).

[Lady Hobbs]

Since I have done all my water changes for two years in this same manner with next to no fish loss in all this time, apparently it's worked fine. I do cap off my water during the week without adding dechlorinator, as well.

Many of the products we use to condition our water contain more than just dechlorinator. They contain what it takes to remove metals and also aloe for the slime coat. A mixture is what they are getting. It's not like each capful is stricly straight dechlorinator alone.

Those that are straight dechlorinator ask for one drop per 10 gallons but contain no other additives.

[gm72]

Totally agreed with Lady. If there were a certain toxic level of those products, Lady's fish would all be very dead by now.

[Lady Hobbs]

Especially as often as I do water changes.......and large ones.

[Chrona]

Well, I'm glad you don't mind supporting the dechlor companies but I'd rather keep my hard earned money in my own pocket.

The question wasn't if it's worth it. Of course it's not worth it to pour all that dechlorinator in, and I even made a point to note that at the end. The question was can you overdose and the answer is no for the most part.

If you ONLY put a full and proper dose of dechlor in your tank when you first start it up. For example purposes, lets say the dechlor solution is 1ppm (I know that is high but it's a simple number for example purposes of this reply). Then do a 50% PWC, you would remove 50% of the dechlor also. Then you add another full dose of dechlor instead of a 50% dose when you add the removed 50% of water. This now increased your dechlor solution by 50% or up to 1.5ppm. Then your next 50% PWC, you would remove .75ppm but add 1ppm with the redose so now your dechlor is up to 1.75ppm. Then your next 50% PWC, you would remove .875ppm but add 1ppm so now you're up to 1.875ppm.


Keep going with this. It's pretty basic math. You hit a theoretical maximum of 2 ppm (tapers off), or twice the concentration of what you put in each time. This is how the EI (estimative index) for dosing fertilizers in a planted tank works.

Over the course of a year, you will be up to 5ppm and then 10ppm, etc.

See above. Start 10 feet from a line. Walk 5 feet, then 2.5 feet, then 1.25 feet, etc. You'll never hit the line (theoretically). You'll certainly never go by it.

At what level are you happy with? Do you think your fish can eventually live in 50% dechlor? I don't!

There is no reason to have to rely on overdosing dechlor to control ammonia/nitrites. These are things that should be handled by regular PWC's and proper stocking of a tank. Sure the dechlor companies tell you to do that so they can sell more product but it's just another chemical they are trying to sell to solve the minor issues that should be solved by providing frequent PWC's, filter maintenance and proper ecology in a tank.

The use of Seachem Prime is for emergency purposes like I said in my post. Even if you did 2 consecutive 50% water changes, you'd still have 25% of the original toxins in the tank. Prime can take care of that. It is by no means a solution for continued use.

Certainly, for folks with chlorine/chloramine treated tap/source water, it is a necessary chemical, unless they want to age the water long enough to allow the chlorine/chloramine to outgas (4days/20days) but I don't mind using this relatively safe chemical at the minimum safe dosage in order to be able to do regular PWC's on my tanks without having buckets and buckets of aging water sitting around for weeks on end (I have chloramines in my water).

My argument was why you CAN overdose without issues. not why you SHOULD. I agree with you that there's no need to be putting in 2-3x the dosage each time. And your argument against my concentration babble is proven wrong by a little math.

[gm72]

Good information backed up by solid facts. Well said.