Salt!

Okey- just readed abou chemical and biological filtration??? What on earth, are u using this as well,ah much to learn

You are showing a Hang on the Back filter (HOB) which are fine for smaller tanks (like yours). The only filters that "clean" under the gravel are Under Gravel Filters (UGF), and they have some issues. You need to be very diligent in your gravel vaccing, otherwise you lose flow through the filter and they are useless after that. There are also REVERSE under gravel filters. Personally, I'm not interested in either since they don't work with sand, and my cories need sand. (They are also problematic with planted tanks as well.)


I use two Penguin 200s on my 56 U.S. gallon tank, and I'm very happy with it. The flow could be a little higher, but to be honest, I don't think it needs to be any higher. If needed a powerhead can always be added to a tank to increase circulation. And if a sponge is placed over the intake, it can be used as filter as well - just be sure to squeeze out the sponge regularly to prevent blockages.


The simplest to set up is a HOB filter - these are also fairly easy to maintain and are fairly inexpensive. The externals are best (necessary for larger tanks), but are a little trickier for a newbie to set-up, potentially messier to deal with if you don't know what you are doing with the hose connections, and far more expensive. Then there are internal filters which are very similar to the HOB filters, except that they stay IN the tank. These are best for smaller tanks. If I were you, I would go for a quality HOB filter (or two).

Ill take a look tomorrow and then ill upload or name the filters i can get and then give ur opinion about the filter,i had seen a nice big one, about 20cm across,not too expensive.. Should i leave my other filters in the thank aswell?

Marius said:

Okey- just readed abou chemical and biological filtration??? What on earth, are u using this as well,ah much to learn

Click to expand...

Chemical filtration is NOT necessary 99% of the time. It is the carbon or zeolite in your filter. These are useful for removing meds from the tank, but certainly aren't necessary day in and day out. Biological filtration is THE most important aspect of the filter. Biological filtration is the bacteria in your filter converting ammonia (toxic) produced by the waste of your fish, excess food, dying plants, etc. The bacteria convert ammonia to nitrite (also toxic), then another type of bacteria converts the nitrite to nitrate (not toxic or even harmful until it reaches REALLY high levels).


This is the SINGLE most important function of the filter. This makes the tank SAFE for the fish. The mechanical filtration is important to make the tank look nice, but really isn't important overall. Any detritus that is picked up by the filter needs to removed by you when you rinse the filter in old tank water. Furthermore, any detritus that is not picked up by the filter needs to be cleaned out by you during your weekly (or semi-weekly or biweekly) water changes. You need to siphon up the gunk off the substrate - benefit of sand is also that the gunk sits on the top, rather than not falling through the cracks in the gravel. If your filter doesn't have the bacteria (biological filtration) working properly, you fish will slowly (or not so slowly) poison themselves.

OKey i get that,i checked out a filter today the one in the pic

And i have yet another problem,some of my fry isnt looking good,theyre
tail fins isnt open,dont know how to explain,i cleaned my gravel yesterday
and a water change about 10 percent,what could be wrong? It cannot be amonia
and the other fish in the same thank looks good,its a seperate part af the thank
and theres a pump that slowly pump water from one side to the other so the water
is the same in the whole tank.