[MacFan]

The photo linked from this post is of a 20g tall tank that housed a colony of Butterfly Goodeids (amecus splendens) covering several generations, plus a few plecos and cherry shrimp. It's a soil substrate with gravel on top. It has CO2 injection when the lights are on and two Eheim hang-on box filters. It is jam packed with Val and had some java moss, a piece of driftwood, etc. We fertilize PMDD.

A few days ago we had a sudden and unexpected die off of all of the Goodeids in this tank as well as 2 of 6 large Angel fish in a 60g planted tank. The next day the other 4 angels died.

The initial night we discovered the die off, we did probably 2.5 tanks worth of water changes with RO water. Last night I vacuumed the goodied tank and did a 70% water change. i also combed through it and pulled all the loose plant matter out. While I probably beat up the plants with the vacuum tube, this Val was a weed and quite durable. As you can see, it's on the verge of melting completely. Why?

https://flic.kr/p/2785259469
The only commonality is that the tanks where the die offs occurred were dosed with Flourish Excel the night before. The Angel tank got a double dose and the 20g tanks (a few of them) might have gotten triple, though not intentionally. If that was it though, it doesn't explain why we had no trouble with our 240g tank which I also double dosed and it has Discus and other more sensitive fish. The only difference is that the 20g tanks and the 60g tank didn't have the lights on for the following day The 60g was actually covered with towels in an attempt to stop some new algae from taking hold, and apparently the tank smelled foul when uncovered. So I'm thinking maybe the Excel killed off algae and/or bacteria that led to sulfur dioxide? Why is the val melting? I've seen it happen once before, when I put jungle val into a brand new 72g tank that took a while to get established. The rest of the time, it's a weed.

Michael
http://aquaticobsession.blogspot.com/

 

[jmontee]

I can't say for sure what happened in your tank without the benefit of parameters but one thing could be an ammonia spike or increase in TDS from the dying vals.

Fluorish Excel has been found to be very detrimntal to vallisneria species and if you had that many vals in your tanks then the die off and resultant melting could have completely thrown off your water quality. Do some measurements of ammonia, nitrites and nitrates and this may help you determine the cause. If the majority of plants was vals then when they died there weren't enough plants to keep any ammonia in check.

 

[MacFan]

Sorry, I forgot that. I didn't test water until we had done many water changes. But last night I tested and found 0 Nitrites and 0 Nitrates. I didn't check ammonia. Tonight I checked and found GH was 40ppm (2.24deg) and KH was 20ppm (1.12deg) and pH was 6.8. What it was before the water changes, we'll never know. The 60g tank last night tested 5ish Nitrates (from the fertilizer) and 6+ phosphates even after several water changes. The 60g had no Val. Now that you mention it, I guess I have seen adverse effects to val from the Excel. Have you seen any problems with Excel and HC? My HC growing emmersed in a bog area outside my 240g tank was growing great and went south turning black in some areas. I picked out most of the bad stuff and it has recovered some. It looked like it might have grown so dense that it lifted away from the substrate and perhaps lost its water supply. Phosphates which were off the charts for so long in that tank have finally dropped to the point where I have to add some to keep things in balance. I guess I need to go back to testing more often.

Michael

 

[jmontee]

HC has always been a problem plant for me, in fact I will probably never try it again. I only say probably because stupidity always creeps back into my head when I least expect it. I have been able to get it to grow in small patches then it all dies away, and I use pressurized CO2, 3.5wpg, ferts etc.... I have seen some threads where people grow this stuff like a weed with excel, no ferts blah, blah blah... As you can tell I hate that plant ( really I'm just jealous that I can't get it to grow).

Phosphates at 6+ and off the charts can defenitely be toxic to fauna in the tank and seriously drive algae. How do you get that much phosphate using RO water? Also doing 2.5 tank water in one night with RO water could probably have been shocking to the fish. Anyway, hopefully everything comes back to normal and you can get your tanks back in order.

On a side note I would definitely recommend setting up a pressurized CO2 system for your tanks. You can actually set up all three using one CO2 tank (maybe a 20lber) and you would save yourself a hell of a lot of money on excel.

 

[Bert H]

Excel and vals don't get along, especially in an OD type situation. As to why your fish died, perhaps they were sensitive also?

Any chance you might have had some detergent/soap contamination in any of your buckets, hoses, etc? That could explain high PO4.

 

[ombcat]

Had you disturbed any of the substrate before dosing the tank?
wilma

 

[rich815]

sounds like the excel dose was just too much. After doing the excel did you move your spray bar to disturb the water surface to help oxygenate the water?

 

[hoppycalif]

Before assuming that you have 6 ppm of phosphates in the tank, be sure to calibrate the phosphate test kit. Those kits are not noted for being accurate. Even if you did have 6 ppm of phosphates it isn't likely that the phosphates caused any harm to either the fish or the plants. Excel, dosed at multiples of the recommended dosage is known to harm vals and a few other plants, plus shrimp and a few fish. It is best to follow Seachem's recommended dosage of Excel.

 

[rich815]

A couple month's ago I was cleaning up some driftwood by pouring excel in it (out of the tank over a tupperware tub). After I was done I did not want to waste all that excel. Stupidly (for some reason) thinking I had diluted it, which I had not, I dumped a good amount of it into my low tech 10 gal. The next morning I had 4-5 of my endler's floating on top dead and my albino cory aeneus upside down on the top breathing in a very labored fashion. He died later that day. Having such a fast die-off in my experience is usually CO2/Excel-related.

And the vals melting is another issue one often sees with doing the over-dosing of Excel. I was trying to get rid of some BBA and did 5x the normal amount of excel in my 72 gal and within 2 days my vals started melting severely. The BBA went away though!

There is a balance between over-dosing excel to limit or kill BBA but not so high as to kill your fish. But to kill the BBA it will almost always be too much for vals so if you have vals I do not think the over-dosing of excel to treat/kill algae is a good option. And any time one cranks up the CO2 or overdoses the excel often it's a good idea to get the surface water rippling to get more O2 in the tank for the fish or even add a bubbling airstone, at least temporarily.

 

[MacFan]

Yea, I've definitely used Excel at the normal and higher doses without problem previously. That's why this was so surprising. As with many disasters, there were probably multiple factors at play.

I do have CO2 injection on all the tanks mentioned. I'm not dosing Excel for that reason, I was doing it for off-label use as an algaecide. I hadn't made the val correlation with it though. Guess I had always used it at lower doses in those tanks.

Michael