Sick Algae Eater

Question
Hello! I hope that you are able to help. I am extremely concerned about my fish tank. Over the last week or so I noticed that two of my fish were developing faint white spots on the tips of their tails. I thought they may be getting ich. About two years ago I had an outbreak of ich after adding new fish to the tank and these spots look similar. I immediately added about 5 tbsp of aquarium salt.  The the day before yesterday I noticed my algae eater acting funny. He laying in a different part of the tank and did not react to being fed an algae pellet. He also just didn't look good, but I cant really define that except to say he didn't look like my "normal" fish. Then today when I got home he was on the side of the tank.  I first noticed that his nose look like it was rotting out (literally, the hole are twice the size they usually are)and his fins looked bad. Then I went around the tank to check his body for anything else abnormal and he had a HUGE gash in his belly. It is probably around 1 1/2 inches long and looks very bad. I honestly cannot believe he is still alive. My algae eater is by far the larges fish in my tank and I cannot fathom another fish did this. Also his nose and fin looks so bad and rotted.  I have no idea what to do.  I have had my algae eater for over 8 year and have never had an issue with him (no even when I had an ich outbreak) I have been to Petsmart to seek advice, but they think I have several different issues going on and sold me treatments for them all. Obviously salt is not doing the trick, but I would love to save my algae eater if possible and I just don't know about adding all these chemicals to the tank, especially at the same time. I am also scared my other fish are going to become this sick as well, so I want to treat ASAP. Maybe treat one at a time?? If there is any advice you can give I would really appreciate it.  

55 gal tank
PH and ammonia reading say normal. (I have an all-in-one reader I purchased for the tank)
temp 79

Fish:

6 cichlids
2 tetras
2 unknown?? sorry I'm not sure what they are.  Some type of tetra I think
1 Algae eater

I know it's a weird mix but all my fish have lived together for at least 2 years.  Two of the tetras were purchased 2 years ago when one of my algae eaters died.  All other fish have been in the same tank for 8 years.
This is what Petsmart recommended and I purchased:

Fin Rot - Melafix - antibacterial remedy
Ich - Kordon Aquarium Rid Ich Preventative
Tetra Lifeguard All-in-One Treatment (this is for anything else it could be)

They think the Algae eater was attacked by another fish.

Answer
Hi Teresa,

Toss the Melafix in the garbage.  It's a waste of money.

If you combine all these chemicals in the tank, you are literally going to poison your fishes to death.

I am not surprised Petsmart employees sold you all this for dosing your tank, but it is not only a chemical bath but it's a waste of money.

The only product you need is your Kordon - and I have another suggestion.

I'd like you to spotlessly clean your filter and take out 50% of your water prior to treatment.

Put in one teaspoon of marine salt per gallon.  That's 55 teaspoons during this treatmet.  That will stop any fin rot from developing or progressing, but I suspect you have a parasitic infestation of both, Ich and possibly a worm (which ate through the stomach of the algae eater).

This may still be in the tank, so let's get the Kordon in there ASAP and follow strict directions.

Return the other 3 products to the store and tell them that an expert online toldyou that not only were they overcompensating, but that putting your fish into this chemical bath is more harmful than good!

This happens everyday.  They mean well, but this is a good way to expire the entire tank.

If you are able to remove all the fish and hospitalize them while you thoroughly clean your 55 and re-cycle it, I recommend that.  The Ich from years ago will systematically return again and again.  They live in the tank forever until either starved to death, or til the tank is spotlessly re-cycled.

I recommend the latter.  Clean it spotless and leave it fish-free 2 weeks to a month.  During that time, it will cycle and the fishes will go home to a speckless new tank.

No more worries! Meantime, put them in a hospital tank with heat and filters and medicate them there.  I do recommend medicating everyone and if taking the 55 down and re-cleaning it isn't possible, then please, treat the entire tank.

Write back if you need further assistance and good luck with this.  I will cross my fingers for your fishes.

Happy fish-keeping.