Guppies are history, new platies, and what to do with 5-gal tank

Hello all! Well I am now guppy-less I only had 5 left, and it was apparent that they were all going to die, so I did the humane thing and euthanized them. I couldn't stand to watch them slowly die. So now I have an empty 5-gallon tank. I have broken it down, scrubbed it all out, including the gravel, which is now sitting on a towel, about totally dry. I have the heater and filter stored in the tank until I figure out what I am going to put in it. My son just asked if we can make it into a salt-water tank. Is this a viable option? I know I'd only be able to keep one or two fish in it, but he would love it!

So I now have two 10-gallon tanks. One with a pair of red mm platys and their babies, which I think still has whatever "problem" the guppies had, because I am losing babies and also a cory cat this morning. The other 10-gallon tankd has a green female platy, to which I added today a pair of blue platys. I noticed that the female blue platy was flashing against the bottom!! Should I add salt??? I don't know what to do, I don't want to go through with them what I went through with the guppies and am still dealing with in the other tank. I do at least a 30% water change every 4 or 5 days in each tank. Should I raise the temp of the water, now it's at about 82 or 83 degreees.

well if the babies are showing signs the guppies did i would suggest useing the 5 gallon as a quarantine tank and put the babies in there. no point in getting the healthy ones sick as well.
Also you might want to do water changes more often then 4 to 5 days if they are getting sick.

How new is the 10 gallon tank?

Have you cycled the new tank? Tested the ammonia and nitrite levels?

Im no expert So im sure other members will beable to help you but im sure they would ask the same questions as i just did.

Let us know

hm what's your ph?what's are the value of nitrate,nitrite and ammonia?what is your filtering system?pls answered those questions...

Did you cycle your tank? The nitrogen cycle is critical to maintaining a healthy tank. It wasn't a good idea to wash out the gravel since it probably had a lot of the beneficial bacteria residing on it. I would not suggest starting a reef tank on such a small aquarium because nano reefs are very difficult and are even more sensitive than freshwater tanks.

reef tank in this small set up!!!!!!!!!!!!!!!!!!!!!!!!!!!to maintain a saltwater tank first you need live rock,live sand(caribsea) and proper lightning..then you have to wait for 1 month to cycle it..more importantly you must need a filter in this saltwater tank,which you may not provide for 10 gallon tank...

Based on the problems your fish are having, it does sound like the aquariums were not cycled before you added fish. I just read an article about cycling in Aquarium Fish International; they say you can add a small piece of raw fish or shrimp to kick start the cycling process. Of course, live plants also help, and they don't smell as bad as an old raw shrimp.

Cycling an aquarium before adding fish avoids big problems; fixing those problems can be complicated and time consuming.

Assuming the aquariums were fully cycled and the fish were gently moved (drip acclimated) the source of the problem is an introduced disease or parasite. Sometimes, they take a week or more to manifest themselves.