Is my tank going to crash?

[lukkereynolds]

Hi all I have had my saltwater 20 gallon for about 3 months and after lots of trial and error I had 5 snails a hermit crab 2 clownfish and a peppermint shrimp , my filter had been broke for about 2-3 weeks until I fixed it yesterday , I have had a massive brown hair algea problem I completed about a 75% water change and got my tank up and running again however the shrimp and clownfish have now died… I am Bassically just looking for advice on where to go from here I have the lights off for 2 days to not encourage algea growth straight after the water chnage but the corals are alive just not open ,, am looking for advice Bassically on where to go from here

 

[T-J]

Are you using some type of canister filter?
Please post all of your parameters. Actual recent numbers, not just "parameters are good".