What's eating my echinodorus cordifolius?

Echinodorus cordifolius (radicans sword) is a large, fast-growing sword plant used in aquariums and outdoor ponds. In ponds, aquatic moth larvae and pond snails cause visible leaf damage. In aquariums, algae on the broad leaves is the primary nuisance. Its fast growth rate helps it outcompete algae better than slower Crypts.

Holes and ragged margins on the very large leaf blades; populations boom in warm, nutrient-rich water Add assassin snails or yo-yo loaches; remove snails manually; avoid overfeeding tank fish

Oval leaf fragments cut out and spun into underwater cases; characteristic neat elliptical cuts Introduce pond fish (goldfish, rudd) that prey on larvae; hand-remove visible cases; apply Bacillus thuringiensis if needed

Algae coats the broad leaf surfaces and tangles around petioles in low-flow areas Improve water circulation, reduce photoperiod, add nerite snails or Amano shrimp; remove heavily fouled leaves