Hmmm…get something larger than a 7L, then? Perhaps I will get a 20l tank to keep the adults in and then remove a pair to breed them in one of the 7L’s. Thankx for the quick replies!
Another question: it is common practice in aquarium circles to take certain water tolerant house plants (such as pothos or lucky bamboo), rinse all the dirt off their roots, and then stick them into a fish tank so they will grow, absorbing nitrates and the like in the process. Would this work for paros? If not, which aquarium plants could serve this purpose? (I am cursed about water sprite…I always manage to physically break it 🙁 ) I was thinking a houseplant could escape issues caused by the tannin stained water reducing the amount of light available.