The hyacints and lettuce seem to be fading, edges of the leaves are drying up and curling. There are no fish in barrel. Nothing else has changed. It has come on suddenly. Could this be a lack of nutrition?

Roj, how much sun are they receiving? Is there any algae growing?

I'm not too familar with barrels, what was it previously used for? Is anything else growing? How warm is the water?

5-6 hours of sun a day

Whiskey barrel is lined and is used this way every year. The only difference this year is that I have no fish in it.

Water is quite clear and cool to the touch (no thermometer)

Only a very slight amount of string algea

---

I put some Miracle Grow in it this morning. I don't know but I'm thinking that they just need to be fed. I hope it will not cause a problem.

I dunno, Roj. Maybe it does need some nutrients. Everything else sounds okay to me; maybe a little more sun (direct that is), but I'd think 4-5 hours direct would be sufficient.

Since the only difference is lack of fish, the floaters probably need more nitrogen and phosphorus which you can add via a liquid pond plant food. In ponds with fish where the water hyacinth and water lettuce don't do well, it's often a lack of potassium. I sometimes add potassium from a liquid plant food. Miracle Grow should help them to grow but you may get more algae too. The proportions of nutrients I think are a little different for something like Miracle Grow made for terrestrial plants and aquatic plants.