Hi I'm looking for a bit of advice on what best to do with the below situation. My tank is a tropiquarium 55 which has a filter electrically connected to the tank top. Its plugged in all the time which works my filter and heater. There is a switch on the tank top for the lighting. The filter is Hagen (3 inserts Carbon, biomax and sponge) and the media that should go in is called trio 2000, this is no longer available from any sources (the past few years I have been lucky to pick up the odd piece of media off ebay but have struggled recently). I emailed Hagen who got back to me to say they no longer stock it and they couldn't offer any possible alternative. Anytime I clean/rinse the media it is in tank water that has been syphoned out the tank. Ideally I would like to remove the filter and put in a new one. However, I'm not very techy savvy and am wary of disconnecting the electrics and messing up my tank. A new tank is out of the question (due to the Mrs My tank is a regular rectangle shape and 10 gallon, can anyone recommend a potential filter replacement. I have looked online and seen some for approx £30 but for every good review theres seems to be a bad one too. I think my current filter media is now causing harm to my fish, most of which look fatigued and are lying on the bottom of the tank. The reason I think my media is the cause is I do regular water checks and the last one showed ammonia levels at 0.25 (never had this before) everything else was fine. There was no food lying in the tank and I do regular water changes every 3/4 days. I have ordered fluval replacement media from amazon in the meantime in the hope it fits in my filter. I am doing daily water changes which seems to perk my fish up temporarily and I have cut down on the food, giving only a pinch and making sure it is all eaten within 5 minutes. If the replacement filter media works I am hoping there will be no need to replace my filter but if it doesn't can anyone recommend a suitbale replacement. Also, does anyone have any further tips to try and keep my fish alive until the fluval media arrives. When it does arrive I know not to dispose of all my present media. Sorry this is a bit long winded reading it back and I have went off in a tangent at points but I'm just trying to explain the situation before wasting peoples time with responses. p.s. I have approx 9 guppies, 3 neon tetras and 2 kuhli loaches in my tank.