Old plastic cards ( ie credit/store cards) are good as make shift algae scrapers for both glass and acrylic tanks. For most algae they will suffice.
Purchase of wadding used in quilts etc by the roll works out far cheaper (by a country mile) over aquarium branded filter floss.
Make your own filter socks as well with felt. DIY tutorial on here.
Egg crate. Stuff is a god send in this hobby. I have an aquamedic blenny tank. One of those all in ones. The only issue with it was the back filtration compartment.
It wouldnt take a filter sock without sacrificing something else. So i built with egg crate a small filter box. Cable tied together. Using some of the floss mentioned earlier it captures a lot of particulate waste and reduces skimmer bubbles (see picture).
Save money with smart purchases and try to avoid the bug if buying because it's meant to be good.
GFO I only buy generic stuff. Keeps cost down. Works well enough for me.
Activated carbon. I have two types in store. One cheap grade lager pellet (bought in 5 litre tubs). I use a handful with GFO in reactor and change weekly.
Rox 0.8 in filter bag (roughly 300ml), passive usage. Change monthly.
This way the good stuff isn't refreshed as often especially as it has a higher absorbtion capability. Whilst the cheaper can be tossed out weekly but does have a higher contact time with water passing around it thanks to the reactor.
Algae scrubbers good addition. Cheaper than running a bunch of chemicals if the rock ain't up to it.
Basically try not to get caught in the whole chemical cleaning process too much. You end up paying a fortune and dablling all to often. That in itself can run risks of causing water quality issues.
Though one addition which is liquid gold in my opinion is the reef prodibio biokit reef. 30 vials which will last just over a year at 60 weeks. Keeps nutrients low with bacteria and adds iodine and strontium.
The difference with this is that the water looks crystal. It's not exepensive either in my book and bi weekly dosing is not labour intensive.
Buy the equipment you want sooner than later instead of cheap then upgrading.
I can testify to this myself. Went through a number of jebao rw4 and 8 pumps, a jebao cross flow and WiFi controllers before buying an MP10. I'd of saved a couple of hundred quid just buying the MP10.
Happy reefing.