Are water changes a must?

Hi everyone,

Sorry to sound dumb, I'm new to this hobby and haven't been able to find a good answer to this question.... But why are partial water changes important? I understand that water quality is important to livestock. But what exactly does a water change do that isn't already being done by filtration, protein skimming, etc...

Thanks in advance!

 

correct me if i'm wrong but i think that it replaces essential minerals and such that skimming could actually remove from the tank....

 

Hmmmm... you would know more than I do. But if that's the case, it wouldn't seem very logical as some people use reverse osmosis in their tanks which basically strips all minerals from the water. Any thoughts?

 

To begin, water changes are the most effective form of filtration. They indiscriminately remove everything in the water...from algae fuels such as nitrates and phosphates, to gill burning ammonia. These nutrients can build up in a system and quickly get out of control, especially in smaller aquariums. A protein skimmer, phosphate reactor, and a deep sand bed can all remove nutrients, but each has their own set of limitations. None of these are 100% effective, but a water change is a lot closer to being that effective. You can remove all of the water from your aquarium and replace it with new, phosphate and nitrate-free water. Water changes also add to the stability of your system. By not letting harmful nutrients build up, the water quality stays stable and your tank's inhabitants can thrive.

In addition to removing detrimental nutrients, a water change can replace exhausted elements. If you have a reef aquarium, the corals will remove certain elements from the water as they grow. These include calcium, magnesium, potassium, iodine, and a whole assortment of other items. This holds particularly true for reef tanks dominated by hard corals and clams. Hard corals absolutely suck up calcium, magnesium, and alkalinity...so much so that systems with these corals usually have a calcium reactor supplying calcium, magnesium, and alkalinity or the hobbyist will manually dose each substance.
;D;D

DIDNT LOOK VERY HARD

 

us biologists have a saying, (it could go for aquarists too)...the solution to pollution is dilution!!!

 

Cool, thanks for the info. Your explanation was technical and I don't understand everything you said. I'm new to the hobby and my ignorance proceeds me. I had thought that cycling a new tank had to do with letting the water establish itself, removing ammonia, nitrate, etc... and water changes appeared contradictory to me but thanks for clearing up my misconception. I'm going to look more into it though. Thanks a bunch.

 

jamie666's explanation was excellent. Maybe I can condense it a bit.

The main difference between the ocean and our reef tanks, is that "Every aquarium is on the way to becoming a box of marine manure if not controlled." (Goldstein, Marine Reef Aquarium Handbook).

All the filtration in the world, along with protein skimming, phosphate reducing etc., is not going to prevent the buildup of wastes in the aquarium. Nor will it prevent the depletion of necessary components in the water. Water changes help get rid of the wastes, and replenish the key components used up by corals.

 

for a reef its a must imo, a few people here skip it all together and only dose very important elements. this is bad way to do it in my opinion as eventually all those trace elements will get used up, and your corals will suffer from it. some people dose trace elements too. this is a bad way to do it also in my opinion as there arent test kits for all the traces so you cant tell if your lacking some elements or have to much of another kind of element, in the long term this could just as easily screw up your parameters.

you spend probably more then 400 dollars for even a small reef tank do you really want your corals to suffer because you couldnt do a 10-20% change weekly to replace elements.

a water change isnt the most efficent way to remove alot of nutrients in the sense you can only remove percentages of the nutrients, but there is no other way to replace trace elements and have some sense your elements are staying atleast close maybe a little below what there suppose to be at.

in FO, you can probably make it to a 10% bi yearily, as i dont think the elements are as important to fish as they should get most nutrition from food, this is assuming you have a nutrient export that keeps your nitrates and phosphates in check.

 

I have to add my argued opinion here...
I never say anything because I know people swear by it, like religion, and it always starts wars, just like religion.
I have never, repeat never done a water change ever. I have added water to replace evaporated water using tap but my water has been checked and is pretty damn close to distilled water.
I have been doing this since I was 10. I watched my father struggle with his tanks and try his damnedest to get certain things out. Constantly changing water and ripping apart rock work and disturbing the tank. I have grown SPS very hardily with adding strontium, magnesium and calcium. I have never added DTs and I am a firm believer in letting the ecosystem balance itself... stop moving stuff and stirring everything up! If you keep flipping all that fresh water in your tank you keep throwing off your cycle and pouring the chemicals in there and burning your coral. I used to test every other day and went through kits like crazy. I have brought my water to other people to check and I was getting tired of hearing "it's fine, what's the problem?". I say I have no problem, just never changed my water and wondering why everyone does?
Now I do believe in RODI systems if you have crappy water... I just don't need one in my area. You can very well top off with Tap and I have been doing so for my whole aquarium experience.
People change their water because it's what they've been taught to do and have incorporated. There are studies showing how it adds this and that and keeps you from getting this or that or fueling algeas and phosphate/ nitrate. If this is totally the case, WHY CAN MY TANK BRING DEAD CORALS BACK? and why can I support other people's dying corals? My tank picks up the bio-load and some how magically brings the dying coral back full vibrant. I am not trying to be a smarta$$. I am just showing that it is very well possible to maintain a tank with out doing water changes... not knocking those who don't mind spending the extra money to make or buy water, salt, RO canisters... who make a gallon and waste 5 down the drain (you should use it for laundry btw). Water is scarce enough, why waste it? I will continue to keep my 18+ year old water and keep groing LPS, SPS and bringing other peoples coral back to health just to prove, atleast to me, it is not a NEED. People believe everything they hear in the news and let big words steer their ideas and beliefs just because it sounds smart. What ever happened to those who believed in the plenum design?? That kinda went out and was found a waste too wasn't it? My tank is healthy and has been doing fine. I have never had a crash or unsuspecting issue in the 18 years of doing this. My friend does his water changes religiously and funny... he's got some undetectable issue. He lost 3 Acro and others don't look so hot. Guess who is going to bring them back???? ... AGAIN!

The theory is if you over feed, it isn't all eaten and your fish poop more.
One, you shouldn't feed so much... and if you do, then maybe you should be pulling out water with all that food you just wasted to help control something.
Two, if you feed normally and watch what can be consumed in minutes... what ever your fish eats and is digested will be picked up and further broken down by your "poop-eaters".
Back to the theory, If you over feed you get more poop eater because the food is there to support it's population (much like bristle worms)... supply and demand. When you cut back your over feeding, the food supply goes down and can't support those "poop-eaters".
LET YOUR ECOSYSTEM BALANCE ITSELF!
Eventually it will balance for the way your habits are (feeding and chemicals). If you get algae, there is a creature in the balance of every ecosystem that eats that (emeralds, sea hares...)! Too much poop... someone eats that too! Make every purchase a critical part of your ecosystem!

I cannot say enough that I have never done a water change and I support alot of organisms. There are those who do it their way and there is me who believes my way. I know my way works because of my journey and experiences. I don't knock those who do it their way because that is their religion/ belief/ system... it's their tank to do it their way. (So, for those of you... please take no offense to my way)

I am going to make a bio just about my journey and experiences for those in question.

 

I only top off, I do a water change about every 3 months on my 90g and still it's only about 10 gallons, I run a sand bed in my DT, a DSB in my fuge, skimmer, PO4 reactor and calc reactor
my coral growth is excellent and everyone has an opinion on this but I dont really have any issues with doing or not doing water changes