you have to use your hands....
of coarse if clean gravel.
Every week so your fish can feel like their at home.
Remove some water using a gravel washer, then replace. I suggest no more than 2 gallons at a time.
To clean debris that falls in the gravel, you should buy a gravel vacuum available at pet stores. You should use the vacuum during each weekly water change to keep the debris to a minimum and avoid making your fish sick.
No because they stick to the wall of their tank and clean the walls of the tank.
== If it is Algea you should empty the fish tank and put the fish into a bucket. Then you should clean the tank after that i would recommend buying sucker fish and a under gravel filter as i had this problem!! if it is not this i recommend going to a fish store and asking them about it!!!
I have two Bristlenose catfish and they are doing a great job of keeping the tank crystal clean. I would definitely recommend these.
You catch and remove the crays (If necessary remove all rocks branches etc first). Then you can syphon out the water and remove the gravel (Substrate). Clean and/or replace the substrate after the tank has been scrubbed clean. Then clean or replace all the rocks branches etc. Replace or clean (at most) 80% of the filter medium and refill the tank. Add water conditioner if necessary to remove chloramine/chlorine, adjust temperature and return the fish/crayfish to their home.
First get a bucket of water, and put the same volume as is in the bowl in the bucket. Let the bucket sit over night, and put water conditioner in it. Net the fish out of the bowl, and put it in the bucket with the new water. Rinse the bowl out, and sponge the inside to remove any algae. Clean, and put back the gravel and ornaments. Pour the water and fish back into the clean bowl. DONT USE SOAP.
with a good enoungh filter and some speicies of loach u should not need to change gravel they also sell vacuums that can clean food and algae out of gravel. hope I helped <3
Fish tank yes? Did you clean the gravel?