I need help ending a debate on water changes!

[Megatron]

Alright so heres the deal:
As I have mentioned before I work at petsmart. Now when you get 6 or 7 people who all have fish and think there way is the best you are bound to get conflicts. One of the latest ongoing conflicts is regarding water changes and my recommendation on them. I personally tell customers to do at least a one 25% water change a week along with a gravel vacing. I also tell them to make sure the temp is the same so there is no fluctuation and to use a good water conditioner. Most of my co-workers claim that this is wrong and that the average person does not know how to do water changes without stressing the fish and that when they do their rare water changes they lose fish. They also say doing water changes upsets the cycle. I know this is completly wrong. Some of my co-workers tell customers to do as little as 10% per month! :thud:
But it is true that often people have trouble with fish dying after they do a water change... its a very common complaint. What I seemed to have determined is the people who lose fish after a water change don't do them that often to begin with therefore it would alter the waters chemistry enough to kill the fish. If you go months without doing one and then take out 25-50% of the water of course that is going to be a drastic change. But people who keep up their water changes weekly or more ( I do 3 or 4 per week) also have great luck with there fish and do lose much less fish in general. Anyways basically what i was thinking is this: If you do frequent water changes ( one per week or more) the water from your tap is very similar to that of you tank or at least close enough that changing 25% is not nearly as stressful to the fish as going a month or more without doing one and suddenly taking out 25-50%. Most people on this site seem to agree water changes can only be a good thing and in my experience I whole heartedly agree.

I would like to know peoples opnions on this issue so I can shut up some of my fellow co-workers who will correct me in front of customer im helping most of whom have way over-crowded tanks anyways and doing more water changes can really only help them. I'm meen come on if a customer comes in with an algae problem 9 times out of 10 they only change their water once a month or less doing more water changes is the most easy answer to give and 9 times out of 10 it works!

BTW the poll is multipul answer so pick one for how often and one for how much.

THANX!

 

[MaryPa]

Most of my small tanks get 15-20% WC weekly.My larger tanks get WC Bi-weekly about 10-15%


Please tell me all these fish aren`t in the same 25 gal.tank.

__________________
My Crazy Tank

25 Gallons
4 Rams
1 Zebra Loach
3 Gold Gouramis
2 Opaline Gouramis
2 Platinum Gouramis
6 Otto cats
3 Aeneus Corys
2 Leopard Corys
1 Raphael Cat
9 Serpae Tetras
3 Red Wag Platys
3 Angelfish
3 Pearl Danios
1 Dwarf Gourami

 

[Megatron]

yeah... they are.... but they are all fine. I do as i said 3-4 25% WC per week have tons of plants and filtration. The other thing is I work at petsmart if it were not for that tank a ton of them would be down the drain if I didnt take them in. There is also no aggresion between my fish and they all look amazing. That being said im getting at least a 65 gallon... most likely right after christmas.

 

[CajunCC]

My angelfish get about 25-30% once a week or so. The discus gets about 50% every other day. I'd do both tanks more often if I wasn't so lazy.

 

[got_nailed]

This will be a good one. It all rolls down to the type of fish, size of the tank, type of filters, amount of food fed, type of food, and how good your tap is. I don’t know if I would base your oppion off a poll like this.

 

[Archangel]

Perhaps the tap water has too much chlorine. This was a problem w/ setting up my 90. I started out w/ 2 Zebra Danios, and every time I'd do a water change one would die and I'd have to replace him. Now I treat my tap w/ dechlorinator before placing it in my tank. Haven't lost a fish since.

I always use cold water on all of my water changes. Never had a problem.

When I first started keeping fish, I had to move, so I moved my 10 gallon to my friends house(I was sorta homeless for a month) but I didn't stay there and he didn't have a clue about fish. All I told him to do was feed them. A month went by. I came for my tank. Put the fish in a cooler, filled w/ (very) dirty aquarium water. So far, everythings fine. All the (9)fish are alive. I start filling the tank up w/ cool water at my new place, and slowly pour in the water from the cooler and add the fish(by this time, lots of nasty crap from the gravel comes floatin out, and I mean alot). Boom. (7) fish instantly die. 2 more lived for a while. My pleco was the last to die. It looked like he had burns all along his body(maybe amonia burns?) and he started to grow alot of fungus on his tail. He died during medical treatment :sad

Still not sure exactly what caused it, but thats my theory. Similiar to your once a month big water changes?

 

[Fishsmurf]

As many changes as is needed to keep nitrate less then 10ppm, once have I have a handle on that as a % for any given tank thats how much I change with the frequency that is required.

 

[bayoupr]

I do my African tanks twice a week because I have them heavily stocked.

 

[happychem]

Wow! 10ppm! That's a new lower benchmark! Well done!

That doesn't work for me, even on my low tech plant tank NO3 never gets above 10ppm in a week. I do around 50% at least once per week.

I actually just had this argument with a guy at our local aquarium club (I swear Halifax aquarists hold on to myths like nothing I've seen!).

You're absolutely right about keeping the tank water as close to source as possible. You could also explain that in the wild fish have a near constant water turnover, so the more that they can change, the better, while matching temperature, of course. You don't need to worry about matching pH because if you're doing enough water changes (i.e. your tank water chemistry is close to tap) then pH and hardness are going to be the same in the tank as the newly added water.

On the other hand, if you leave the tank a long time without water changes, or with only very small ones (I maintain that a 10% change isn't worth the effort to get out the bucket), then the pH and KH in the tank are going to be very different in the tank than from the tap. Ditto things like TDS (Total Dissolved Solids) and unmeasurable pollutants like organics, fish hormones, fatty acids, sulfur compounds, phosphates (which are measurable), and
sterols.

Or you could argue stability. Let's imagine that each week the fish add 100 imaginary units of waste and that each week you change 50%:
After one week: 0 - 100 -> now you remove half
week 2: 50 - 150
week 3: 75 - 175
week 4: 88 - 188
week 5: 94 - 194
week 6: 100 - 200
week 7: 100 - 200
You tank will remain stable at about 200 units of whatever is being added after about 2 months. Now try it with 10% changes! (don't wanna? I already did it)
In the same example the tank levels off at about 1000 units after about 66 weeks!

Granted some of these will be consumed by heterotrophic bacteria, but not all and these bacteria are not 100% efficient, nothing is, so there's still some bi-product of bacterial metabolism.

 

[Blinky]

Well said, Happy.
I change 50% once a week to keep everything balanced in my tanks - this seems to be the general rule for planted tanks, and I figure if it ain't broke, don't fix it!

Megatron, I wonder if you could try illustrating the issue to customers/colleagues in human terms - imagine 25 people smoking in a room, and once a week someone opens the door to remove 50% of the existing smoke-filled air and let fresh air in. Now the air is 50% cleaner, and it's easier to breathe. Now imagine that room if someone waited three months to open the door, and then only a crack for just a minute! That's what a 10% water change might be like in a heavily populated tank.
It was much clearer in thought