i want to do it right this time

Question
QUESTION:  ok for many years now, i have been fish keeping but everytime, my fishes keep dying from disease or some other reasons...the bottom line is, they jus keep dieing even though my ammonia nitrite and nitrate lvls are all good..that is ammonia 0, nitrite 0 and nitrate 10-15 ppm..i have a 20 gall tank with a cycled HOB filter with a bio wheel...my tank is also planted...my few questions are :

1) how to prevent fish diseases?
2) how often to do water changes and by how many percent?
3) do i need to vaccum the gravel to suck up the fish poo or jus lift the water siphon tube in the water?
4) what to do when fish is sick
5) how to check if fishes are healthy at the store.

and finally...

6) what should i do when bringing new fish home?

pls help me as much as possible ..thanks

ANSWER: Hello Charistance:  Fish disease is prevented by maintaining your tank through regular water changes and gravel vacuum/cleaning your gravel... as well as by providing a healthy diet that is varied to include brine shrimp, tubi-worms, and a quality flake food or pellet.  Water changes should be done at a minimum weekly with about 10-20% of the water volume being replaced.  The gravel must be cleaned at least monthly and in newer tanks... about every six weeks.  If you have a lot of fish in your tank then clean the gravel lightly on a weekly basis.  The plants help a lot to keep the gravel semi-clean.  Fish poop should be removed for the most part.  When fish get sick the best thing to do is to identify what is causing their sickness.  Treat accordingly with the proper medication and remove the carbon filter during the medication time frame. Change 50% of the water when the medication cycle is complete... and add beneficial to your tank afterwards.  What I do when I buy a fish is this:  I look at both eyes to see if they are clear and active not cloudy or not moving.. fish should be alert.  I look at all of their fins for signs of shredding, missing parts, or even a white edge to them. I look for active fish and most importantly I go to the fish store with my tank water chemistry and I ask and sometimes insist that they check the tank chemistry that I want to buy a fish from... You want to make sure that the two water chemistries are not too far apart.  If it is an unknown type of fish for me then I do research first before I buy to make sure it is compatible with my tank and the fish I have in it.... I hope this helps... dave

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QUESTION: hey daivd..thanks alot for the info...i have 1 queation on my mind though...u said that the gravel should be cleaned...but the problem is..underneth the gravel in my tank is a layer of soil pellets that i use for my plants...,the trouble is, when ever i stir the base of the tank, the soil pellets would also be stirred and there would be many many soil particles floating around in my tank, manking it hazy...the soil pellets that im using is very breakable and partciles of soil would break away from the pellets with the slightest commotion...what should i do? thanks

ANSWER: Just hold the gravel vacuum over the top of the gravel and the debris on the top will be siphoned away... there is no need to disturb the gravel if you have flourite under it...dave

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QUESTION:  U have been a great help for me....one last question i would like to ask...my tank is planted with live plants...do no know the names of these plants though...but one thing im veru sure of is that the plants that i have are not thriving...the leaves are browning and most of them are dropping the leaves on a daily basis..i give them CO2 tablets as well as plant nutrients...they also have enough light as my tank is placed in my balcony and when it is night, i leave a light on...however the plants are still not doing well...any advice? thanks

Answer
I would make sure that you have a plant bulb in the tank. Not all light bulbs will grow all kinds of plants.  I would also make sure that your water chemistry is ok.  Some aquatic plants take nutrients from the water and not from the soil. I would also leave the light off at night... Plants need to rest too and during the night they absorb oxygen and release carbon dioxide.  During the day the process is reversed.  Keep me posted.. dave