Don't waste money on specialist cacti plant food, anything with high
potash low nitrate like tomato feed is ideal. And don't over feed.

Perhaps less obviously let the compost dry out between waterings and
give generous amounts of water but never leave them standing in water.
This is a lot easier with very open grit based compost on staging.

In mid summer and active growth they can need almost as much water as
normal houseplants (but will survive with much much less). Succulents
can be a bit more touchy about watering especially in the recent
heatwave.

Regards,
--
Martin Brown

I have a 100g pack of "Chempak" cacti food cost me £1.55. Been feeding my 20
cacti with it for over a year and there is still another 6 months of feed in
the tub.

I have mine in 80cm long plastic troughs, not the ideal thing to grow them
in, but they are a perfect fit in my windowsills.

Eanest Trawler