Temperature is a little too high - advice?

The temp in my tank is currently reading 22-23c which is higher than I would like it to be. It's likely to get warmer here in the UK and I don't want to risk harm to my lotls.

My options, as I understand it, are to either go for a mesh lid/fan combo - although this is likely only to reduce the temp by a few degrees - or buy a chiller. I'm leaning towards the latter, although they're pretty costly, but at least I'd know they'd be safe all year round.

my tank is about 75 gallons - what size chiller would I be looking at to best keep it cool? I know nothing about setting up chillers (I'm an axolotl novice and in fact an aquarium novice, having ended up with these guys accidentally) I have a hang-on filter which cascades water into the back of the aquarium. Will this work with a cooler?

Please forgive the daft questions!

Yeah I use a chiller in the uk too and it's very handy
You simply need a chiller which is rated for around 300 litres
I'd recommend a hailea hc-300a
They're comparatively cheap but high quality

Chillers do not have pumps though so if you don't have an external filter you need to get a pump in your aquarium with piping going into the chiller then back into the tank
Check the specific chiller for the recommended flow rate and get a pump which has similar.

thanks for the recommendation! I'm saving my pennies as we speak to get it in time for the weather warming up.

another daft question - what kind of pump will I need for the hailea hc-300a? I'm a total novice with aquariums of all kinds. I have a Marina S20 slim hang-on filter which I guess is going to be no help.

It needs a flow rate of 1000-2500 LPH (Litres per hour)

Just look online (e.g. Amazon) and search for a 1500 LPH pump or around that power

Make sure you take note of the outlet size for that particular pump so you can get appropriate tubing

Looked up your filter and just want to clarify

Is your aquarium 75 Gallons (G) or Litres (L)
Because 75 gallons is almost 300 litres

If your aquarium is 75 Litres you only need a Hailea HC-100a and a pump flow rate of 200-1000 LPH

you know I realised I had no idea what the size of my aquarium was (it was given to me) so I measured it and checked via a volume calculator tool and apparently it's actually 96 litres/25 us gallons (lengh 80cm, height 40cm, depth 30cm) - I have no idea where I got 75 gallons from! I feel quite silly now. I imagine I'd need something bigger than the 100a, but not quite as big as the 300a?

There's the HC-150a which would be good
It needs a flow rate of 250-1200 LPH

just a quick update - I picked up a Hailea 150a from a website which offered a Hailea pump into the bargain. Had a bit of an issue connecting the tubing (the pump required thicker tubing than the cooler - it leaked all over the place until we tightened it with clamps) Just in time too, because the weather has taken a turn for the hot here in London and while I sweat at 29c, the lotls are nice and cool at 19c. So far it seems to be working beautifully - fingers crossed!

One question, if anyone knows: I've used a small metal ring clamp to hold the tubing in place on the pump. Is this safe to be in the aquarium?