Hi vicvel , I seldom come here. So, pls forgive me if the folowing comments does not matter anymore. I too have just begun rearing the LH (Luo Han) since 2 months ago. However I've enough experience as an aquarium fish-keeper. I'm also a koi-keeper. Like koi, we should try to provide best water conditions to our LHs. This means water free from ammonia, nitrite and minimal nitrate level. It is also a pleasure to have clear aquarium water. At present I'm using 2 types of filters for my LH aquarium. One is the undergravel filter and the other is the above aquarium box type filter. I find these two combinations very effective in removing ammonia and keeping water crystal clear all the time. A siphon is used to suck out the waste from the gravel easily. The LHs just love to move the gravel here and there. Good exercise for them. I use the siphon twice a week and in the process replace 50% of the water. I clean the box filter only once a month as not much waste is found there. I prefer the usual aquarium with the coral sticker as background as figerglass 3D takes up too much precious space. It is easier to fix the undergravel filter too. I prefer plain fluorescent lighting but I do add a little Black Water concentrate after each water change out. This causes the water to appear very slightly brownish and is very soothing and pleasant to look at. Black Water extract softens water and is good for the fish. I also add abit of salt each time after a water change out. Of course, care must be taken to dechlorinate the water. I'm using a powerhead to supply the filter box and also to create alot of oxygen bubbles in the aquarium. The undergravel filter is supplied by the airpump. The best way to reduce nitrate level is by regular water change outs. LHs eats alot and produce alot of waste. Regular 50% water change outs to remove the waste also reduces the nitrate levels. No need for any elaborate nitrate removing device. Keep the hobby simple and enjoy your LHs!