I thought you were doing 50% every day, that's what happens when I read several posts at once
Sorry about that!As far as filtration, you obviously can't remove the filter you have on now because you'll remove your biological filtration (the very small amount you have) which you took SO long to build up. You can however add a second filter.
I would go with either an AquaClear 300/70 or a penguine 200 or 350. Any of the smaller AquaClears, Penguins, or Emperors would help your tank BUT higher filtration is usually better, as most people overestimate the amount of fish they can keep (that wasn't derogatory, just honest, I made that mistake too at one time
) If you have the money a good bet is one of the models Rena makes. These are standard canister filters and are much quieter than most HOB models, plus have a lot of biological filtration capacity.
About the only way you can get away with light filtration (yours would be considered EXTREMELY light), is to either keep a very heavily planted tank (something most people don't have) or almost no fish load.
There is not too much filtration as long as the amount of water flow isn't so high that it impedes your fishes swimming ability. Fish are healthier with "too much" filtration rather than not enough. "Too much" won't cause your ammonia and nitrite levels to skyrocket and it will allow you to stock a normal or slightly heavier fishload.
A note on your current filtration:
Gallon ratings on filters are useless. By this I mean when they say "Rated for - 5-10 gallon" "10-20 gallon" "20-30 gallon" etc. it means nothing. Companies decide their own ratings based on who knows what.
You have to look at the flow rate, with and without media. This tells you how much water the filter pulls in per hour without filter cartridges and media, or with filter cartridges and media. Some companies will try to fool you by only listing GPH ratings WITHOUT media, you have to read closely.
Another thing you must look for is media capacity, type of media, and consider the type of filter (whether HOB (hang on back) power filter, HOB canister filter or normal canister filter).
Cheap HOB filters don't hold enough media, or the right type, to build a sufficient bacterial colony, this means you must stock very few fish or your ammonia and nitrites will stay high. Cheap HOBs such as the Aquatech also don't supply enough oxygen to bacteria to allow them to grow. Quality control is shoddy, some don't even work at all. We had one that never cycled, and the first one even had a hole in it causing all the water to come out.
HOB filters with biowheels, or HOB filters that have room for your preferred media (such as the Aquaclears) are much better. Some, such as an EMPEROR 400 has room for media AND has a biowheel. These aren't very expensive and filter much better than the cheap HOBs.
Normal canister filters are the best as far as media capacity, and generally filter more debris out before needing maintanence. They also allow you to put your spraybar anywhere in the tank you prefer. They do however cost more money than HOBs, so it depends on your needs. If you are planning a planted tank a canister (not the HOB kind of canister though) is a good idea since it won't cause surface agitation which will dissipate your co2 (of course now I'm getting too technical).
Anyway, this is why people don't ask me about filtration, lol.
