# Help! overdosed my tank



## dougbraz (31 Aug 2021)

BY MISTAKE, instead of dosing my EI mix (which I pour into a shot glass of 50ml), I poured 50ml of Seachem Excel into my 30gal tank! I have been dosing daily with 10ml and the tank is looking very good in my humble opinion and humble expectations, but now I am worried having clearly severely overdosed Seachem. I have no inverts, just a few fish and quite a few low tech plants.
Should I do a large water change??


----------



## foxfish (31 Aug 2021)

if you are at all concerned then yes do a water change.


----------



## dougbraz (31 Aug 2021)

Doing a 50% wc right now..


Sent from my iPhone using Tapatalk


----------



## dougbraz (31 Aug 2021)

50 litres changed, fingers crossed..lesson learned.


----------



## plantnoobdude (31 Aug 2021)

if it's been a few days and you haven't noticed any difference in fish activity i wouldn't be too concerned


dougbraz said:


> 50 litres changed, fingers crossed..lesson learned.


if you're very concerned another one or two 50% water changes would help get rid of the residual glut.


----------



## dougbraz (31 Aug 2021)

plantnoobdude said:


> if you're very concerned another one or two 50% water changes would help get rid of the residual glut.


I will observe over the next few days - hopefully no biggie!


----------



## John q (31 Aug 2021)

dougbraz said:


> poured 50ml of Seachem Excel into my 30gal tank! I have been dosing daily with 10ml and the tank is looking very good in my humble opinion and humble expectations, but now I am worried having clearly severely overdosed Seachem.


Short term exposure to high levels of glutaraldehyde should be ok.. don't panic.. l'd be more worried about the long term effects of 10mls daily if I'm being honest.


----------



## MichaelJ (31 Aug 2021)

plantnoobdude said:


> if it's been a few days and you haven't noticed any difference in fish activity i wouldn't be too concerned
> 
> if you're very concerned another one or two 50% water changes would help get rid of the residual glut.


@dougbraz   Yes, just echoing what @plantnoobdude  is saying... if your worried do another one - personally, I would,  just to err on the safe side!.
If you did a 50% WC already your have essentially diluted the overdose from 30x to about 15x (or 10x to 5x relative to your current daily dosing) ... just skip the dosing tomorrow and the day after...

And I agree with @John q  .... 10ml is really 3.3x times the recommended daily dose for a 30 Gallon tank., not quite sure if that is a good idea long term?


----------



## Wolf6 (1 Sep 2021)

I've regularly overdosed with easycarbo, which I think is pretty much the same, and never noticed negative side effects. Just make sure you dont get it onto fissidens directly (it will die off after direct exposure) or some species of vallisneria. I use it as algaecide, dosing it directly onto suspected patches of bba or other algae.


----------



## dougbraz (1 Sep 2021)

John q said:


> l'd be more worried about the long term effects of 10mls daily if I'm being honest.


I have read conflicting info about this with low tech tanks. I agree that even on the side of the bottle it says "do not overdose", so maybe I will lower it down to the recommended amounts and see what happens (now that my algae is under control, apart from many points of small bba. If they stay small, I am not bothered, but if they grow large... 
To be fair, my vallisnerias melted just with irregular dosing on small amounts even! So no more of those in the tank..


----------



## Wolf6 (1 Sep 2021)

dougbraz said:


> I have read conflicting info about this with low tech tanks. I agree that even on the side of the bottle it says "do not overdose", so maybe I will lower it down to the recommended amounts and see what happens (now that my algae is under control, apart from many points of small bba. If they stay small, I am not bothered, but if they grow large...
> To be fair, my vallisnerias melted just with irregular dosing on small amounts even! So no more of those in the tank..


I've heard of people having issues with vallisneria and liquid carbo before, but I had to remove vallisneria nana from a previous tank because it grew out of control whilst dosing easycarbo. I wonder what was different in my tank at the time...


----------



## MichaelJ (1 Sep 2021)

Wolf6 said:


> I've heard of people having issues with vallisneria and liquid carbo before, but I had to remove vallisneria nana from a previous tank because it grew out of control whilst dosing easycarbo. I wonder what was different in my tank at the time...


@Wolf6  yep, I did Excel for while. My mosses and Vallisneria didn't like it at all - and still some experience the opposite effect. I didn't see much improvement with other plants in general, but I do know some people have great success with it - especially in combination with injection. I would never use it as an algaecide though, I know it has those properties, but I'd rather address the underlying issues - which is usually too much light intensity and/or poor flow and circulation, not enough ferts, organic waste etc.    
Cheers,
Michael


----------



## dougbraz (1 Sep 2021)

MichaelJ said:


> I didn't see much improvement with other plants in general,


Funny, my plants grow like crazy with adding Excel. Only vallis melted completely (I tried twice) .I have another smaller tank to which I add nothing now and growth is very slow. When I added Excel, I was cutting back plants radically every week! Some recommend it, others loathe it, others just use it for spot doing on algae. I dunno, I am not ready to add CO2 yet, so I guess we just experiment and see what works. (Also read more)


----------



## dougbraz (1 Sep 2021)

...also _Echinodorus amazonicus _melted away quite rapidly despite being recommended as a hardy, easy plant.


----------



## MichaelJ (1 Sep 2021)

dougbraz said:


> Funny, my plants grow like crazy with adding Excel. Only vallis melted completely (I tried twice) .I have another smaller tank to which I add nothing now and growth is very slow. When I added Excel, I was cutting back plants radically every week! Some recommend it, others loathe it, others just use it for spot doing on algae. I dunno, I am not ready to add CO2 yet, so I guess we just experiment and see what works. (Also read more)


@dougbraz   Sure... I would still like to understand a little bit more of why it works for some and not for others. Perhaps it got something to do with other compounds in the water column interacting with the glutaraldehyde that either makes it work well, not at all or makes matters worse... and why are some mosses and Vallisneria particular sensitive to this (?) etc. I bet some of the water chemistry experts around here could shed light on this.

Cheers,
Michael


----------



## dougbraz (1 Sep 2021)

MichaelJ said:


> and why are some mosses and Vallisneria particular sensitive to this


My java moss grows faster than algae! 🤣


----------



## plantnoobdude (1 Sep 2021)

MichaelJ said:


> @dougbraz   Sure... I would still like to understand a little bit more of why it works for some and not for others. Perhaps it got something to do with other compounds in the water column interacting with the glutaraldehyde that either makes it work well, not at all or makes matters worse... and why are some mosses and Vallisneria particular sensitive to this (?) etc. I bet some of the water chemistry experts around here could shed light on this.
> 
> Cheers,
> Michael


vallisneria have very thin permeable leaves. same with synoganthus and tonina species (sadly speaking from personal experience.) also moss have A LOT of surface area for such little mass which also makes it more sensitive to excel/h2o2.


----------



## MichaelJ (1 Sep 2021)

dougbraz said:


> My java moss grows faster than algae! 🤣


Haha yes, java moss - I'm not surprised!  ... Well, my Pellia  (also known as Subwassertang) which is considered an extremely slow-growing moss (in non-injected tanks at least) didn't like it for sure.
Cheers,
Michael


----------



## MichaelJ (2 Sep 2021)

plantnoobdude said:


> vallisneria have very thin permeable leaves. same with synoganthus and tonina species (sadly speaking from personal experience.) also moss have A LOT of surface area for such little mass which also makes it more sensitive to excel/h2o2.


@plantnoobdude ,  I like that explanation, but it won't explain away why some people claim they had success with  Excel even with Vallisneria and similar plants with very permeable leaves, unless of course it's because they use a very low dose  perhaps, and the Excel hardly made a difference.
Cheers,
Michael


----------

