IMO twig catfishes should not be put in any tank that small sorry (I had the same experience with my first tank when i was younger which was also 65 litres and i wanted a twig catfish) the minimum tank size for ONE should be about 20 gallons but at a push on their own you might be able to have 2 in a 90 litre but thats on their own
I have owned all kinds of plecos from big to small to otos, ALOT
By my experience there are two mega algae cleaners out there and they are Ancistrus (bristlenose plec) and Pitbull plecs (parotocinclus jumbo)
As i said i too started off with a 65 litre tank and i was desperate to have an algae cleaner after the massive regular pleco one shop sold me (saying it was a bristlenose) was growing too big and had to go back. It never really cleaned any algae but i really wanted a hand with it ( i was about 14-15 years old at this point)
After many searches i found a maidenhead aquatics store which specialised in L number plecs and has a big tank full of some tiny plecos, only about 4 cm but 10-15 of them were there.
They were pitbull plecs and they only grow to about 6 cm and they are very like corys in that they hang around in groups ( and should be bought in a minimum of a trio) and sleep next to eachother but they go off and do there own thing too.
I immediatly bouhgt 5 as my tank was seriously out of control algae wise ( and being a young teen i couldnt be bothered to manually clean it!)
The SECOND they got into the tank they got to work rasping at every bit of algae in sight
I was very pleased with them and then went to bed. When i woke up the next morning EVERY SINGLE SPEC OF ALGAE WAS GONE!
I swear my tank was sparkling
yet there they still were cleaning the glass
Not only did i keep them till they died of old age but i absolutly fell in love with the little guys, the best bit was they were entirly peaceful and never hurt anything in the tank during feeding time (like other plecos sometimes do) or any other time they would quite often dive onto my hand when cleaning the tank and stay there 'cleaning me' lol
TO this day i have 5-6 tanks with at least 4 of the pitbulls in each, they may be small but they do the job in a tank of any size in fact in my big tanks i have to now grow algae for them because they have none left!
Dont forget thought that they each other food (infact almost any other food) and they relish zuccini
In a nut shell Pitbull plecs are WONDERFUL fish and brilliant plecos for anytank whether you just want them for algae cleaning or not i am sure you will quickly fall in love with them.
P.S. another great thing about them is there colour they are actually like little fishy chameleons! Depending on where they are on the tank or what they are on (and whether they have just been fed) they change colour depending on how they feel!
I have had some go a beautiful gold colour while others go grey and mossy green
I thoroughly recommend this pleco to anyone
/www.brighthub.com/pets/freshwater-aquarium/articles/80059.aspx
) anyway since adding the Bulldog i haven't had any algae and she has quite a character too 
