I've tried allot of substrates over the last 5 years and filters my personal choices. Small tanks 18" sort of size 2x foam filters the £3 kind driven by dual outlet pump one each end. Pickup well and with a sand substrate easy to clean. Sand is just enough to cover bottom nothing much. 2ft-3ft tanks - External pumps - My favourite I JBL E series they take the JBL bio nitrate media in very well and it actually works meaning 1 water change a month is enough. CO2 is an issue as you need to ripple the surface to get rid of the gas the bio media emits. Nose pegs required when cleaning pumps. Pre filters need to be done every 2 weeks. Media my favourite has to be quartz rounded. It's simple it hides debris meaning you don't feel the need to weekly VAC the tank and it seems acceptable to most basic fish I keep. Plants can do okay in it. The water change method - This is new to me. 1 100L water butt with stand (£20) 1 hose pipe to with tap fixing on it one end and a weighted on the other (Stops the hose flipping out top when filling the water butt or splashing around) - (£20 adapters cost ) 1 pump height max of 1.6m (£25) 1 hose pipe with clip on attachments to allow quick connect to pump and one to allow wedging in cover glasses or lid (£12) 1 x siphon kit (£12ish) 1 x pipe work at angle to drain outside with hose pipe clipped on with jubilee clips. (£30) Sounds allot and it is expensive to setup but wish I had done it earlier. The drain kit means once its going I can have a coffee and just remove it when done to right level. The water butt comes down night before filled and treated left with air pump on it to move the water a bit. Pump it back into the tank while making sure you run the pump dry. Removes the heavy lifting doesn't do it any quicker with cheap pump but I'm not doing the muscle work. The prices are rough from memory but it is one lesson I have really learned the hard way. Spend the money on the kit before the fish as it makes a big difference to the time you have to enjoy them.