I overfed my 40 gallon aquarium. 2 of my tiger barbs died. it warned me. so i researched the sickness and did a 50% WC and added quick cure. Luckily my Cichlids did not get infected well my convict was being less active but it did not have visible signs. I think my Cichlids will be okay. it is defenetly overfeeding. for now on i will feed those fish less. my water is always clear I juts think food go in the gravel witch attracted parasites. there were also little worms on my glass. I will add salt later. just DO NOT overfeed your fish! I am pretty shore it was costia.