i believe sparkling gourami will eat them. but i assume they would also eat baby shrimp?

 

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I want to try Planaria Zero, but nobody in my city carries it (stock for fish meds in general is very low right now). In my 10g they only show up on the front glass, as far as I can tell. I just use a razor blade to scrape them off the glass. They stay away as long as I don't overfeed. I think mine came in from some floaters I bought from a local guy on Kijiji.

I don't think there's a fish that will eat hydras but not shrimplets. However, snails will eat hydras according to that link.

 

What about a tiny microscopic fish that could out compete the hydras?

 

Pretty much any fish that would eat Hydra will eat your shrimp fry.

Planaria Zero works really good, but it is hard on Nerite snails if you have any. You'd need to move them to another tank and then not put them back for a few months, after some major water changes. I got it on Amazon.

 

Anyone had experience with snails eating hydra? My ramshorn snails seem to try to avoid them. But maybe I got cowardly snails.....

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Last I heard, it was bladder snails (Physa sp.) that ate hydra. Basically, if the fish can "peck" at the glass, it seems to me that the fish might be well suited to eat hydra (sparkling gouramis, mollies, etc.). However, if the fish is large enough to eat hydra, then it's probably large enough to eat shrimplets.

I know you don't want to dose "chemicals", but do want to leave the following link in case it gets too hard. Since I'm going to be feeding heavily, I've decided to just preemptively treat for snails and hydra anyways.

Kill Planaria & Hydra

Kill Planaria & HydraKilling Planaria & Hydra with FenbendazoleDisclaimerWarning: Using chemicals in the aquarium can be harmful to any of the inhabitants. This article should be used as a reference for experimentation and not as a 100% safe method to kill Planaria and Hydra. Please use...

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