Crayfish molting about every 7-8 days, planaria question

[bulrush]

I have some smaller crayfish, which appear to be juvenile O. virilis. After having them about 6 weeks, and feeding them regularly, both crayfish molt every 7-8 days. This surprised me that they molted that much. OTOH, they DO appear to be juveniles, and they are eating a lot.

I feed them 1 shrimp pellet each twice a day. They eat it all so I have not reduced their feeding. Sometimes they get a quarter of an algae pellet (instead) since o. virilis likes algae too. They love string algae but I have not gotten string algae from the stream as I found, when I put it in a dish once, it was infested with planaria.

How will planaria affect a tank?
Will crayfish eat them?
Do they carry disease?
Are they just annoying?
Will they eat snail poo?

[CanadianCray]

Ok first off. 1 shrimp pellet each once a day is more than enough for juv. crayfish. Even if they eat it all crayfish will over feed themselves because in the wild they don't find food every day & this continuing on a daily basis can harm your crayfish aswell as water quality. It is common for juv. crays to molt frequently as this is when they are growing the most. It should get progressively longer between each molt. If not then something is causing the molts like water temp too high or excessive feeding. Feeding your cray too much can lead to premature molts & soft shell.