Help not sure what this is!!!

[Kkamanu]

Hello all. Brand new here. I have a 20 gallon tank. Last night or of nowhere the beta fish we had developed very bad fin rot on his tail and he had white specs on him. The tetras we have also had white specs. Fearing the worst I assumed it was ich. Went to get ich medication from pet smart as they were the only thing open. I ordered ich-x on amazon will be here tomorrow. Unfortunately we lost the beta but the specs are gone from the tetras and they seem to be doing fine. I come home from work today and notice this fungus looking thing. Please let me know what you think it is and what I can do to stop it. My ph test last night was approx a 7.6.

 

[Essjay]

The white fuzzy thing on the gravel looked like uneaten food that has grown fungus.

White specs that look like salt are indeed ich. Although the spots have gone from the tetras you need to keep treating the tank as per the medication instructions. The ich parasite has three stages and can only be killed in the third.

The stages are -
Attached to fish. We see this as the spots. The casing round the parasite stops the med killing them
On the bottom of the tank in a cyst where they multiply, and again the casing stops the med killing them
Free swimming - the cyst opens and tiny free swimming parasites go looking for a fish to infect. This the only stage that can be killed so there must be some med in the water when the very last cyst opens.