From Seachem: “Will the Flourish Excel™ kill the Vallisneria or will they adapt over time as some people suggested?

We had received reports from several hobbyists who said that they had seen Vallisneria melt when Flourish Excel™ was used with them. We also had reports of them thriving with Excel. Because of this, we decided to do an experiment to test this in our lab. First we did a preliminary study with several val species (Amazon val, Italian val, corkscrew val, contortion val) with three tanks with different dosages: double dose, recommended dose, and a control with no Excel.

In that initial experiment, we did see some melting of leaves in the tank receiving the double dose, though the damage wasn't extreme and new leaves grew in strongly to replace the lost vegetation. In the regularly dosed tank, we didn't see any issues. This was a short term experiment just to see if we could see an effect and based on the results, we launched a more carefully controlled experiment where we tried to more carefully determine the best guidelines for using Flourish Excel™ with Vals.

We were able to make a few generalizations from our experiments and what we have heard from hobbyists:

1. Large doses of Flourish Excel™ can sometimes cause some melting of the leaves of Vallisneria. The larger the dose, the more likely there might be an issue.

2. The damage is temporary; the roots aren't affected and it grows back strongly and tolerates future dosing of Flourish Excel™ even at higher than recommended doses.

3. Vallisneria normally tolerate the regular maintenance dose with no problem. In both experiments they weren’t affected by the daily dose, only higher doses.

4. When other nutrients (nitrogen, phosphorus, iron, potassium) are dosed, Flourish Excel™ doses could be much higher without melting any leaves of the Vallisneria.”

It's how you interpret this data that matters, something Greg left out is not obvious here, which is the way these plants grow.

This is the key phrase:

"we did see some melting of leaves in the tank receiving the double dose, though the damage wasn't extreme and new leaves grew in strongly to replace the lost vegetation."

When you plant one of these plants, if it's big and undamaged, you'll probably be able to retain it.

But, what I"ve seen from every species f val and sag possible to get is tht the primary purpose of the plant is to send runners.

It will do that at the expense of its own self which is a viable strategy.

So, a lot of the time when you get a plant that he been damaged ("brown at the crown" of the leaf) or is small it may in fact not grow ever and will concentrate it's dwindling resources into making a runner so the next generation will have a chance.

So, guys that buy 6 plants and deicide they are dead just lack patients. Leave them alone and they'll surprise you. Notice when you pull those up there's little tiny runners there.

Now, read that again:

"we did see some melting of leaves in the tank receiving the double dose, though the damage wasn't extreme and new leaves grew in strongly to replace the lost vegetation."

There are two possibilities there:

1) Excels kills val but makes it grow faster at the same time, a contradiction, so it can not possibly be true. What can you really say here? "Well it kills val but makes it make lots of new pants faster than without it"? Maybe you just lack experience with val perhaps? Note this is always new val put into a tank. Nobody tries ths with established wall which is nev set back or killed. 2) New val, may sometimes die. Only about half the time did I get a new plant to survive, many seem to waste away and die bit - and this is the important part - only after they've established root colony and sent up at last 4 new plants. The plant does not "die" it is recycled. This is because the leaf tissue in that plant was not made in that particular water and is different enough it makes new plants in that new water it know will survive. Crypts do this too. Now, if you two tanks that are the same then transplanting one to the other does not result in death in either Crypts or Val.

2) Excel speeds up the process of growth, so what the pant would do normally, still happens, just faster. It helps when judging these tings to understand the natural life process of the plant in question.

rjs Jan 2019