fish kill preminition

[mountain_webste]

ammonia should be 0 at all times. if you have ammonia spiked, you will have nitrites spiked at some point when the bacteria catch up.

Good point. Planning another H2O change this evening as well to be safe. Curious to see how my test kit reads. To your earlier point, it is very old.

 

[GoldLenny]

I generally dose excel between 6 - 7pm when I get home from work, but on water change days I will wait until I'm adding the new water which usually ends up being a bit later, 8 - 9. I've followed this same routine with both my tanks many times before without incident. Both tanks are on timers with lights-off between 11pm and midnight.

My only thought is that I may have inadvertantly added too much excel. Maybe, to your point, this was the perfect storm of an accidental higher dose, a little later than usual. Though this is a 165G tank and I just completed ~30% water change. While I didn't measue, it's not like I added a cup of excel or anything. Per your suggestion, I'll ping Seachem to see if they have a suggestion. Oh, and I'd been using this same bottle of excel for a month or more on both my tanks so I don't suspect a tainted/bad batch or anything.

I just can't imagine what else could have caused it. Temp was stable, amonia even after all the deaths was <.025. I didn't test for nitrites, but I have no reason to suspect a spike since I did nothing to the filtration and had just completed a large water change. Every other aspect of my water change routine was normal - vacuming for waste, method and amount of water treatment used etc., etc.

The PWC could be just as suspect as the Excel.

Have you baseline tested your tap water before? If yes, you could test it again now. See my blog article "Find Your Tap/Source Water Baseline" for more details.

Water utilities can change the source of our water from time to time throughout the year and this can affect things dramatically for some folks.

You could go from having a higher pH tap water to a lower pH tap water without them telling you anything. You could go from having a higher CO2 level tap to a lower CO2 level tap without them telling you... and this CO2 level will usually be the cause of the pH change... although the utilities could also change their buffering formula and that could also change things.

I know my tap water 48 hour baseline ranges from 7.2 pH to as high as 7.8 pH depending on the time of the year.

IF.. and that's a BIG IF... something was changed recently that caused your tap water pH to be much lower than you would normally expect and then you do a 30% PWC with this much lower pH, you could have changed the pH too much, too fast for some of the fish. IF... your tap water had a much higher CO2 level, contributing to the pH drop, and you did a 30% PWC, both the big drop in pH and the high level of CO2 could have been a cause.

Of course, you should have seen something in the couple of hours that you were still close to the tanks and the lights were on... but it could have been a combination of a possible pH drop, CO2 rise and the Excel overdose... combined with the lights out later on, that caused the problem.

I hope you can come up with a more definitive answer so you can take steps to prevent it in the future.

Last but not least, you should update your signature. You are still showing the 165G as under construction. I didn't want to say anything but one of my first concerns were that you had WAY TOO MANY fish in your tank... but I didn't say it since you were feeling bad enough... but I'm glad you finally mentioned this was in your 165G tanks so at least it wasn't an overstocking resulting in a shortage of O2 issue to compound things.

 

[excuzzzeme]

You actually need ammonia but in a very small amount. You don't want to exceed .25. The ammonia is a catalyst to keep the BB fed. Most test kits do not register that low.

 

[GoldLenny]

I should add, for anyone else reading this thread and for your future reference, whenever your fish are showing signs that something is wrong.... or if you have a fish death, or a catastrophic even like yours, it's really good to get test results for everything to at least be able to eliminate things as a possible cause. It might not change anything but it would be nice to know if your pH had crashed last night due to excessive CO2 levels from the tap water. By now, the excessive CO2 levels would have outgassed and the pH would be back up to normal.

 

[GoldLenny]

Good point. Planning another H2O change this evening as well to be safe. Curious to see how my test kit reads. To your earlier point, it is very old.

Did you do PWC's on your other tanks also... or just on the 165G? That might help to eliminate the tap water as a possible cause. If you didn't do PWC's on your other tanks, then I would hold off on doing another PWC until you know your tap water test results and baseline.

 

[mountain_webste]

Did you do PWC's on your other tanks also... or just on the 165G? That might help to eliminate the tap water as a possible cause. If you didn't do PWC's on your other tanks, then I would hold off on doing another PWC until you know your tap water test results and baseline.

Thanks for all the feed back Lenny, it helps to think through all of the possible issues.

I thought about our earlier conversation this evening and I doubt it was the tap water. I had done a water change of 30+% in my 46G on Saturday, no issues. I also did a 50% w/c last night immediately upon finding the dead fish. 24 hours later everyone that survived Sunday night is still fine.

Also, regarding the few comments on amonia levels. The reading was less than .025 (the lowest my kit goes), NOT .25. Retested tonight and the result is the same. Sorry if I made a typo earlier.

 

[GoldLenny]

It looks like it could have been a combination of things or possibly just the Excel although, as others have also said, overdosing Excel should not kill fish. It's done all the time as a way of combatting algae. Now, Excel can kill some plants but it doesn't usually kill fish.

Let us know if/when you hear back from Seachem and their thoughts.

 

[mountain_webste]

So I e-mailed Seachem outlining the situation and variables discussed in the thread. Here is their response:

I'm so sorry to hear about your fish. Flourish Excel does have reducing properties just like every water conditioner on the market. When reducing agents are used in excess, they can potentially reduce the oxygen in a tank because they do not have anything to bind with or reduce. Since you were using more than the recommended dose of Flourish Excel, along with your de-chlorinator, the reduction of oxygen took place. For future use, I would not recommend using the Excel at the same time as your de-chlorinator. I would recommend waiting until later that evening or the next day to dose the Excel, after using your de-chlor. Again, we truly do apologize for your losses and hope that you will remain a loyal Seachem customer. Please let us know if we can be of further assistance. Have a nice day.

Good to know not to use it at the same time as water conditioner as that has been my proceedure in the past. I would add excel and any trace element supplements into the buckets I was filling; my thinking being that would dilute the additives some before being added to the tank. I would also think that the directions on the package are a bit misleading as they recomend and increased dose following a large water change (presumably with water treatment in the majority of home aquariums).

Live and learn...hopefully my experience will help others...

 

[GoldLenny]

Thanks for all the feed back Lenny, it helps to think through all of the possible issues.

I thought about our earlier conversation this evening and I doubt it was the tap water. I had done a water change of 30+% in my 46G on Saturday, no issues. I also did a 50% w/c last night immediately upon finding the dead fish. 24 hours later everyone that survived Sunday night is still fine.

Also, regarding the few comments on amonia levels. The reading was less than .025 (the lowest my kit goes), NOT .25. Retested tonight and the result is the same. Sorry if I made a typo earlier.

Since your test kit is old, you really can't rely on any numbers that it may produce. I think I posted earlier about this but didn't want to re-read my other posts. LOL Once the bottles, presuming you have a test kit with bottled liquid reagents, have been opened and exposed to air, they chemicals start to degrade and after a year or so, they start giving bad readings. Also, if folks don't shake the bottles enough prior to using them, any settlement that may have happened while it was sitting up causes a bad test result since you are adding drops from an improper mix of the chemicals in the bottle. That also throws off all future tests since the chemicals are no longer in their proper percentages.

Considering the amount of money we spend on setting things up, buying fish, supplies, etc... the $17.00 or $15.00 price tag for a new master test kit every year is a small price to pay... even if you only have to use it once, like in your case, to know what all of your water parameters were in your tank when the incident happened... and for baseline testing your tap water a couple of times a year to make sure they are staying consistent or at least knowing when they change.

 

[GoldLenny]

So I e-mailed Seachem outlining the situation and variables discussed in the thread. Here is their response:

I'm so sorry to hear about your fish. Flourish Excel does have reducing properties just like every water conditioner on the market. When reducing agents are used in excess, they can potentially reduce the oxygen in a tank because they do not have anything to bind with or reduce. Since you were using more than the recommended dose of Flourish Excel, along with your de-chlorinator, the reduction of oxygen took place. For future use, I would not recommend using the Excel at the same time as your de-chlorinator. I would recommend waiting until later that evening or the next day to dose the Excel, after using your de-chlor. Again, we truly do apologize for your losses and hope that you will remain a loyal Seachem customer. Please let us know if we can be of further assistance. Have a nice day.

Good to know not to use it at the same time as water conditioner as that has been my proceedure in the past. I would add excel and any trace element supplements into the buckets I was filling; my thinking being that would dilute the additives some before being added to the tank. I would also think that the directions on the package are a bit misleading as they recomend and increased dose following a large water change (presumably with water treatment in the majority of home aquariums).

Live and learn...hopefully my experience will help others...

I haven't really heard that before... the part in bold above... so I did some Googling and there's not a lot about this on the net. The most common hit came up saying, "Flourish Excel also has iron reducing properties...", but not much about O2 reducing properties. However, I did find these posts on another forum.

Hello all - lurker for some time, brand new to posting here. Great website.

This question has been with me for awhile. My tank parameters are:

20H, injected CO2, 65w PC at 6" over tank, Fluval 205 at max., Koralia 1 at cross-current to the Fluval outflow, both directed towards surface somewhat (very good surface ripple). 55 plants. 5 cardinal tetras (new, and lost 4 of the 9 stocked), 9 white cloud minnows, 1 BN pleco, 3 otos, 5 amanos, a few RCS. pH 6.8, dKH 7.3, NH 0, NO2 0, NO3 10 (measured Saturday, the day before change day).

Prior to injecting CO2, and prior to adding amanos and RCS to my tank, I was using Excel on a daily overdose of 5X (10 ml), with no adverse affects. In fact, plants thrived, no algae. Now, given the CO2 injection and with concerns about toxicity and the shrimp, I have returned to a normal daily dosing of Excel, 2ml/20 gallons.

My question goes to the recommendations for "overdosing" on major water change days. I employ EI and change water at 50% weekly. I am confused over the reasoning involved in this dosing rate, and have concerns about toxicity by this regime as well.

If Excel is either "used" up in a planted tank or otherwise dissipates daily, so that there is effectively no buildup during the week - in other words, on a presumption of a "clean slate" daily, and each day's dosing is to simply restore the recommended concentration - why "overdose" on change day?

Unless I'm wrong on my presumption, and the 5x/1x recommendation is to maintain something higher than the 1X concentration during the week?

At any rate, I'm hopeful someone from Seachem can provide some thoughts on this day 1 heavy dosing, and possible toxicity issues for invertebrates (and sensitive fish species, perhaps, such as my cardinals).

Thanks,

Paul

Seachems reply, since Seachem actually participates in that forum:

Though many people overdose Excel for the purpose of algae control, we as a company cannot recommend it for a couple of reasons:

1. Because our products have not been approved by either the Food and Drug Administration or the Environmmental Protection Agency, we cannot market Flourish Excel as an "algaecide". We have heard from many, many customers that this is an added benefit, however, we cannot actually market the product for that use.

2. Flourish Excel is a reducing agent. Reducing agents, by nature, will reduce whatever is available to reduce in the tank. With that being said, there is usually not an issue, and will be no issue if dosed as directed, however, overdosing in massive amounts poses the possibility of reducing oxygen in the water, especially if there are other reducing agents, such as water conditioners or clarifiers being used at the same time. So, the issue is not due to a build-up of the product in the tank, but simply the nature of a reducing agent. As I said, used as directed, there will be no harm to any fish or invertebrates you are keeping.

Followup question by OP:

Hi - thanks for the reply. Not sure if I spoke with you, or not, but No. 2 is precisely my question - if on day one, the water change day, I dose at 5X the normal dose, or 10 ml/20 gallons, O2 reduction is precisely my concern - in essence, this represents a "spike" of Excel and its reducing power, so I don't understand the reasoning involved in using this high an amount on change day, relative to the normal amount. In my discussion (might have been you), I think we concluded that there is some presumption that Excel isn't fully used up daily, and this overdose represents a kind of parsing regime for the week, but I'm still not entirely clear on the reasoning involved in this day 1 dosing.

Another poster:

From the instructions on the bottle "On initial use or after a major (> 40%) water change, use 1 capful (5 mL) for every 40 L (10 gallons)"

I think the original question of PaulNorth is why overdose (5ml/10 gallons) on day 1 or on any days with water change > 40%. I'm also interested in Seachem reply to this.

If you don't mind, I'd like to ask Seachem my own questions on day1 overdosing.

1. If overdosing and day 1 (5ml/10 gallons) is safe, and if there is no issue on buildup over the week, why can't I just overdose (5 ml/10 gallons) on succeeding days (if that helps control algae considering cost in not an issue).
2. From website "Flourish Excel™ also has iron reducing properties which promote the ferrous state of iron (Fe+2), which is more easily utilized by plants than ferric iron (Fe+3)." If I used Flourish Iron, would iron (Fe+2) be more available to plants when I overdose (5ml/10 gallons) on day 1 compared to the usual dose (5 ml/50 gallons) on normal days ?

Seachem's reply:

Sorry for the confusion on this aspect. The statement that Flourish Excel is only available for 24 hours is a valid statement, but is dependent upon quite a few factors (ie: organic waste present, plant load, etc.). In testing this product in "moderately" planted aquariums, we found that the 5mL of Excel per 50 gallons was enough to supply the plants with carbon for 24 hours. The Flourish Excel also can interact with organics in the system and be broken down. So, the more fish you have (ie: organics), the less Excel that you will have available to the plants. Lets take, for instance, someone who has only a few fish, relatively clean water, and very few plants. It is completely safe for them to use the recommended dose of Flourish Excel (5mL/50 gal), but they may see some buildup of Excel over time. The buildup is not a negative aspect, it means that we are likely maintaining a good amount of carbon in the system. Well, if we perform a >40% water change on the system, we will remove any of the leftover Excel that was in the system. We therefore know that at this point it is completely safe to add the 5mL/10gallons. Many people with heavily planted tanks are able to dose the larger amount on a normal basis, but we cannot recommend this since there are other unknown factors involved with the possibility of buildup. I hope this answers your questions in regard to that.
As far as the Flourish Iron question is concerned, our Flourish Iron is already in the ferrous state so it is in the bio-available form. Since it is complexed with a gluconate, it will remain in this form even in the presence of Flourish Excel.

My thoughts...

I hadn't seen the O2 reducing problem mentioned before so that was new to me. Given this, it seems like the possible or likely overdose of Excel combined with the dechlor (BTW... which product do you use and did you overdose it also? I know most people seem to.) and then turning the lights out a couple of hours later was the straw that broke the camel's back. When the lights were on, the plants were putting out O2 so the fish were still getting enough O2 but once the lights went out, the plants quit putting out O2 and thats probably when it got to be too much. Fish with lower metabolisms or inactive fish were probably not as badly affected as highly mobile fish or fish with higher metabolisms that needed more O2 to keep them going.

At least that sounds like what happened to me.

I would dose Excel in the mornings or at noonish when you turn on the lights in the future and then you can do your water changes, etc. in the evening but remember to still leave the lights on as long as possible after a PWC... just in case! I've never done PWC"s late in the day or right before lights out so I've never seen a problem with doing PWC's but maybe this is why some people think their fish get stressed from doing a PWC... because they have high CO2 in their tap water or they are using too much dechlor (which according to Seachem will reduce O2 levels) and then turning out the lights right after which reduces O2 levels... even in non-planted tanks since all tanks at least have algae and the algae creates O2 during lights on as well as plants.

EDIT - You may want to start a thread on the planted tank forum and add a link to this thread. Of course, they may already have this discussion already.