Help please! Community tank problems!

[Darroe09]

Request Help: please help identify and how to treat?! Pictures below

Tank size: 65 gallon

Water levels: waiting to get off work to check

Fish Symptoms (include full description including lesion, color, location, fish behavior):
2 fish died so far
The rest of the fish have a film like residue on them
There are small short white things on their eyes and body
Fins look like they are rotting
My one angel has darkened his body to almost black.
My one fish is already swimming sideways and bumping into things.

Volume and Frequency of water changes:
25-50% change every 3 weeks.

Chemical Additives or Media in your tank:
Aged tank with fake plants and decor

Tank inhabitants:
3 Angel's
5 tetras
5 longfin tetras
3 cory catfish
Ropefish
Dojo loach
Rainbow shark

Recent additions to your tank (living or decoration):
Catfish: now dead
Rainbow shark
Rocks

Exposure to chemicals:
None

Digital photos:

 

[Essjay]

Can you give us the test results for ammonia, nitrite and nitrate please.

I am not an expert in fish diseases, but the first thing to do is increase your water changes. You need to do a few large water changes every day, then do at least 50% every week. 25 to 50% every 3 weeks is not enough. Most problems are caused by poor water quality so water changes alone might well sort out the problem.
If that doesn't work, you could try adding salt to the water - plain salt with no additives. Use 1 tablespoon per 5 gallons. Dissolve the salt in some tank water first then pour it into the tank.

Could you tell us what country you are in - if the tank does need medication we need to know where you are as medication varies from country to country.

 

[Retired Viking]

@essjay is spot on you need to do a water change every week to keep your fish healthy.

 

[seangee]

The film is a mucous coat the fish produce to protect them from an irritant. Most likely poor water quality as suggested. Do an immediate 75% water change and repeat daily for a week.

I only have a mobile phone with a small screen so can't comment on the white things because I can't see them.

 

[Colin_T]

The white bits on the fish is just excess mucous that is peeling off.

The most common cause of excess mucous is poor water quality or chemicals in the water. As mentioned above, do a 75% water change and gravel clean the substrate every day for a couple of weeks.
Make sure any new water is free of chlorine/ chloramine before it's added to the tank.

Clean the filter if it hasn't been done in the last 2 weeks. Wash filter media/ materials in a bucket of tank water and re-use them.

If there's no improvement after a couple of big water changes, post some more pictures and a short video of the fish moving about and we can look into it more.