Flourish Excel dangerous?

[DanMan]

Does anyone else use Excel in their planted tanks? I've been using it strictly for algae control for several months now without issue until yesterday.
I only use it once a week at most.

So yesterday I did a 75% WC added Excel at 1.5 times the recommended dose ( been doing this for a while to control algae - its supposedly fish safe and i've never had any issues before). A few hours later I notice that ALL of the fish are losing their slime coats and a after a couple more hours 2 of the 5 are laying on their sides. I initially thought maybe the micro-bubbles from the WC had irritated them causing the slime coat loss.

I did another 75% WC and there was almost immediate improvement. This morning, all seems to be back to normal.

Has anyone else ever had a problem with Excel? Obviously I won't OD the tank with it again - but now i'm wondering if I should be using it at all.

[DiscusLoverJeff]

Have you tested your water before adding to the tank? Maybe there was a change there? I use Excel as well and never had any issues. You may of just had a bad batch of water.

[DanMan]

I'm using declor'd tap. I don't test it first.

[DiscusOnly]

Dan,

My only problem with Excel has to do with melting my vals. Never a problem with Excel and fish. I've actually soaked equipments in excel in the past to remove BBA and it never affected the fish. I would be more incline to think that something changed in you tap water.

Van

[judy]

I'm wondering if you forgot to dechlor the water. Sounds like that kind of reaction to me. I use Excel religiously and have never had a problem, not even with my vals, whihc I know a lot of people have reported problems with...

[DanMan]

I'm wondering if you forgot to dechlor the water. Sounds like that kind of reaction to me. I use Excel religiously and have never had a problem, not even with my vals, whihc I know a lot of people have reported problems with...

I'm pretty ritualistic about my WC process so its very unlikely...but a tiny seed of doubt is now planted.....

I had a similar issue once before immediately after a water change and lost a fish - but in that instance only the one fish was affected. This time it was the whole tank. The rummynoses werent so rummy (went pale). My corys were oddly active and playful (seemingly) - they usually save this for when the lights are out.

I really have no idea why. I can't imagine the quality of my tap changed over a 5-6hr period. I only consider forgetting to dechlor as a possiblity because I can't think of another explaination. Again its highly unlikely - i'm a little OCD about the whole process.

[judy]

the only other reason it occurred to me is that like you, I am profoundly ritualistic about the Sacred WC Ritual-- yet I have to consciously move the Prime bottle right to the tank lid by the pump and remind myself repeatedly: add the Prime, add the Prime-- because I once, many, many years ago, did the routine WC on a FOWLR saltwater tank (all they had back then was FOWLR, so that tells you how long ago!) and forgot to add the dechlor and killed a bunch of ridiculously expensive fish overnight. At least, I think that's what I must have done. Everything else was handled the way I always handled it...
Ever since, I have been haunted by the thought of losing my discus this way...

d'you ever just run a test on the tap water for the hell of it?

[lipadj46]

Excel is glutaraldehyde which is used to disinfect medical equipment, so yes it is dangerous and can easily kill fish if used improperly or even properly if other things are off. IMO excel does not work well enough anyhow.

[DiscusOnly]

I'm pretty ritualistic about my WC process so its very unlikely...but a tiny seed of doubt is now planted.....

I had a similar issue once before immediately after a water change and lost a fish - but in that instance only the one fish was affected. This time it was the whole tank. The rummynoses werent so rummy (went pale). My corys were oddly active and playful (seemingly) - they usually save this for when the lights are out.

I really have no idea why. I can't imagine the quality of my tap changed over a 5-6hr period. I only consider forgetting to dechlor as a possiblity because I can't think of another explaination. Again its highly unlikely - i'm a little OCD about the whole process.

Dan,

In some homes, one can notice a huge difference in the water that is coming out of the faucet when the water department does their flusing. I've seen water that looks "rusty" from a friend house after the township did a flush (this is only what one can see). If you don't have one already, I highly suggest getting a whole house water filter installed. I am always amazed by what the filter look like every too months.

Van

[ericatdallas]

Excel is glutaraldehyde which is used to disinfect medical equipment, so yes it is dangerous and can easily kill fish if used improperly or even properly if other things are off. IMO excel does not work well enough anyhow.

I use gluteralhyde instead of Excel and I've dosed my tank 2x recommended dose with no problems. As far as the disinfectant portion, this is correct, but I think you need to add the 'activator' for it to work as a disinfectant.

If you have ever ordered gluaralhyde, you'll see that it comes with a little package with directions to poor into the container before use. If you want to use this as a cheap Excel substitute, do not pour this is and discard it. Although, keep it around just in case you want to sterilize tanks when you run out of bleach, in lieu of bleach, or do do a very thorough cleaning :)

[lipadj46]

Metricide 14 is the one to buy, it is about twice as strong as excel and much cheaper. Fun fact: 10% Glut solutions are used as wart removers also.

[ericatdallas]

Hmmm... I didn't know about the wart remover. Wow, that's some serious up charge...