cleaning tanks at work

Question
QUESTION: The place I work has 24 smaller tanks (i think 5 gallons each) and one larger (15 gallons). It has been a while since they've had someone working in the department to take care of the fish. I'd say it's probably been close to three months since they've been cleaned. Now we have a severe problem with algae growth and our fish are dying at an extremely high rate (sometimes over 100 fish a day). When we try to scrub the tanks there is so much algae built up in the corners and on the glass that the water turns so dark we can not even see the fish, so we have to take out most of the water and replace it. We are medicating them as often as we can but because of company policy we can not take the fish out of the tank to clean them properly. Is there anything we can put into the water to help keep the fish healthy while we try to clean the tanks or something that will kill the algae or even make it easier for us to clean it?

ANSWER: What kind of fish are in the tanks??? What kind of business is it that you work at??? 100 fish per day with 24 five gallon tanks is a lot of fish per tank and that is probably the reason for the fish loss.  I would start also with a water chemistry test to see what the water issues are.  I would put the fish from one tank in another tank and then clean them one at a time moving the fish back and forth.  If you need I am happy to explain to a supervisor the benefits of changing the policy for you.  dave

---------- FOLLOW-UP ----------

QUESTION: There are a large variety of fish in the tanks. The ones I can think of off the top of my head are angel fish, green puffer fish, dragon fish, a few different guaramis, tetras, goldfish, oscars, and glofish. As well as small algae eaters and piecostamous. I don't know if I got the spelling right on a few of those sorry. I work for a large national retail company. We have tried explaining to them that we need to move the fish to clean the tanks properly but they still refuse our request. They say they "would rather loose a few fish than loose customers because of empty tanks." They don't see our point of how the dirty tanks are loosing more customers than if they would see a few empty tanks while we're cleaning them.

Answer
I would talk to the manager and just say... I am going to put the fish in a bucket and clean their tank and then put them back in the tank.  It should not take more then 20-30 minutes per tank and that should appease them... I think that they have the idea that you are going to leave the tanks empty for a while.  All that you really need to do here is to remove the fish to a bucket, wipe the surface of the aquarium with a scrubber, gravel vacuum the water out of the tank and then replace with new water.  Make sure you add bacteria to the tanks as you replace the water.  If you can manage to set up water before hand then do so and add bacteria to it.  We are constantly cleaning fish tanks while there are customers in our store... it makes people come back to us again and again because they see that we take care of our fish.  In this economy we have seen large fish stores close while our business gets better because people come back to where there is quality.  dave