Craig
That is not a great water temperate change in our hot summer days and cool nights my tanks will have a greater temperature change that that.
I would be more likely to think of water quality or the Ram which can be rather aggressive at times.
Filter cleaning, I tend to be rather fussy at cleaning.
Also remember I run a UGF in both tanks.
The Threadfin Rainbow and Shrimp tank 100lt actual water content has an Eheim Pro11.
I can clean the filter every second month if required but I clean it every month.
The 5ft 300lt+ has an Eheim Pro3 will be replaced with the Eheim Professional 3 (its a 4 basket) after I do the rescaping.
It has big Hoplo Catfish, Bristle nose, 1 large 25yld+Clown Loach a few medium sized Clown Loaches and Silver Sharks plus 10 medium sized Aust Rainbows.
Cleaning both filters is exactly the same I have never changed my method for many years.
I remove one basket at a time, the medium (except sponges and filter pads) all get a very good washing in the old tank water to remove all the gunk.
The filter sponges and pads I wash under a hot running tap (that is the only way to clean them fully)
They are then rinsed in old tank water, basket re assembled and placed in a bucket with old tank water.
I take the impeller out, give the housing and impeller a good cleaning.
Next clean the filter container out also under a running tap.
All seal joints are lubricated with a Silicon Grease to stop the seals cracking.
Baskets replaced old tank water used to top up the container.
Next most important I add a "Double Dose" of Seachem Stability to keep the bacteria healthy.
Fix the top on, clamp down and top up via the inlet.
Reconnect to tank turn it on and off it goes ready until the next cleaning.
Over the years I think I have heard every reason why I am doing it wrong, if that is the case why are my tanks healthy, fish live over 20 years, shrimps breeding, plants growing well.
The sponges are a very small percentage of my total filter medium and substrate, it is no different than replacing a sponge of filter pad or a medium in a basket.
I must admit I have had about 47 years experience with fish tanks and that helps a lot.
Keith