Water Changes

[aquafrogstuff]

I have a 150L tank with two discus, black ghost knife, bristlenose, elephant nose and some serpae tetras. Interal filter.

I've read in a discus book (Discus Fish, A Complete Pet Owner's Manual) that 20%-30% water changes are recommended once a month. The book cites improvements in filteration technology being the reason for the monthly intervals.

What's confusing is that many people on this forum do more frequent changes, some every day!! I understand this depends on the population density and other factors, but what is the general rule of thumb ??

[sammigold]

I think once a month you would be inviting major problems. ie. ammonia build up which turns to nitrites which are toxic to fish. I think it is a personal thing... we change ours once a week or more often if we think there is a problem... people with large fish loads require frequent water changes due to more fish/more waste ratios... HTH

[mcloughlin2]

I try to do 20% water changes a day....the water i change then goes in to the fish pond out the back or on the gardens if is to dirty....

It is up to u really but if u want good growth rates u have to do more water changes....

And the more fish u have the more water changes u have to do.....

[Merrilyn]

Our discus fish come from some of the cleanest waters in the world. The Amazon river has a low pH and a very low bacteria count. Here the fish thrive and breed and grow huge.

If we want to get the best from our discus, it's important to try to simulate their natural conditions. A tank at best, is an unnatural home for a fish used to very clean water. Frequent waterchanges are essential if you want to have success with discus.

It's the one rule that you simply can't break.

The cleaner the water, the better the growth, health, and colour as well as breeding success. That's why a lot of us breeders do daily water changes. In fact, on my fry tanks, I change the water twice a day, 50% each time.

[mcloughlin2]

LR out of interest how many water changes should be done on a 4footer with 4 3-4'' discus and some bn..??? To get the best growth rates and to have heathier fish??? :D

[Merrilyn]

With that large tank, and a small number of fish, twice a week, doing about 30% each time would be plenty.

There's no hard and fast rule, but the more fish in a given volume of water, the more waste.

The solution is waterchanges. Some of my tanks are very overcrowded with juvenile fish, so I do a daily water change of about 50% on those tanks.

[DR.V]

One simple rule, the more fish you got in one tank the more water change required.

Because more fish means more poo and it will polute the water ie : high ammonia and nitrate

[endless]

Has anyone used nitrazorb or some kind of nitrate absorber like the seachem types? Do they really work well enough to significantly reduce the nitrate in the tank and hence reduce the need to do as many water changes

[DR.V]

I used nitrazorb and ammonia remover for 1 tank only. Yeah they reduce ammonia and nitrate effectively but I still do regular water changes as I feed my fish beef heart and water will be messy without w/c.

But if you feed your fish with dry food like tetra bits, I think w/c can be reduce to once every one or two weeks.

[aquafrogstuff]

Firstly thanks for all the replies.

Can I gather your thoughts on the best method to do the actual water change. I’ve been using one of the suction hoses to remove tank water and clean the substrate at the same time. I do two buckets which equates to about 20% of the tank. While I’m doing all that, I have tap water filled into a clean plastic bag (bin bag) in the laundry sink. I use a small power head and Sera water conditioner to deal with tap water nasties. While I’m cleaning the tank etc I leave the small power head running in the ‘new’ water in the laundry. Basically from then on I fill the tank with the conditioned water. Process seems to work OK, apart from water drops throughout the house. Wife loves that bit…NOT!

Some people just use straight tap water!! I live in Perth and some people here seem to think the water quality is good enough to run straight from the tap to do a straight change. I haven’t been game.

[mcloughlin2]

I just use the siphon to clean the gravel, then i change as many buckets of water i can then i just fill up a bucket and put water conditioner in the bucket of water and put dip it straight in the tank..... :)