water changes?

[AshStar]

Ok...I have a 125 gallon aquarium...it has a skimmer wall (reef ready) that dumps into a sump box filled with bio balls (not sure what everything is called, i bought the whole system from someone, so I am not sure about how all this works), from the sump box it goes to a cansiter filter then returns to the tank. I have been doing water changes even though all my levels are with in normal range (I don't remember specific numbers atm, but checked it before i did water changes and all the levels were with in normal ranges)...my question is this, with such an extensive fitration system, are water changes are still required weekly? I don't mind doing them, infact, I rather enjoy it...but I don't want to cause my fish any undo stress. It started as a freshwater tank, but I am converting it to a brackish water tank by adding a little marine salt with each water change and will eventually have it a full marine tank for my puffers. I also have another question, is it necessarry to change the substrate from gravel to sand? If so, at what point should I do this and why? ANY input from you guys would be great. I am new to the puffer world...I, like alot of people, bought my 2 original puffers from wal-mart with no information on them. Once I got home, I placed them in my 20 gallon tank and began researching....fast forward a month and I now have a 125 gallon for my guys plus added 2 more gsps for a total of 4. I feed them fresh live crawfish (I live in Louisiana, so I can catch them about a mile from my house), frozen bloodworms, freeze dried shrimp, and shrimp pellet food...not all at once, I rotate what I feed with each feeding... I am having some difficulties getting snails for them. (any suggestions on that would be greatly appreciated)...But I am hoping the crawfish shells are hard enough to keep their teeth trimmed until I find a constant snail source. So to recap my questions--1. water changes necessary? 2. Changing the substrate, when and why? and 3. Where to get snails. My lfs sells puffers so they won't give me snails and petsmart won't let me buy any or give me any because they are not licensed to give or sell them.

Thanks a million for any and all information....I look forward to a long happy life with my beautiful babies!

ash

[Lil' Swimz$]

You SHOULD get some sort of aragonite-type sand/gravels. It keeps the pH balanced.

I'd do sand, just because many SW creatures like sand, and personally I think puffers like the softer substrate.

[Pufferpunk]

Yes, you always need to change at last some of the water weekly. Even if it's only 20-25%--judge by your nitrate. There is no stress involved with doing WC. How big is your sump? When I do WC on my 90g reef tank, I turn off the pumps & change out the water in my 20g sump.

[Flutter]

1. Water changes are absolutely necessary. Doesn't matter how fancy the filtration system is. Good for you for asking though and not just assuming that you don't need to do them I think a neat way to think about it is for us with clothes. You wear your clothes for a day and you're careful not to pee or poop in them (tough I know ). Does that mean your clothes are good to wear out the next day again. What about wearing them straight for a week or two? See, just because you don't use them as a bathroom doesn't mean that there's nothing else getting on them and they remain clean Similar for a fish tank. They release more than just feces too.

2. I'm pretty sure you want to change the substrate once you start going brackish if you haven't already. It helps with the pH (to keep it appropriate) but I don't know anything beyond that.

3. You may need to buy snails online and either keep buying them or start up a breeding colony.

[AshStar]

Thank you so much for the info! I was pretty sure the wc was neccessary so I will keep on doing them! I will change the substrate when I do my next wc (next week), and will keep looking for snails!

ash

[RTR]

Perhaps one of the worst misconceptions in this hobby is that many folk think that filtration and water changes are trade-offs for one another. This is absolutely false. Water changes and filtration are complementary - they do different things to support high water quality in our tanks. Biofiltration is to detoxify nitrogen metabolites which are otherwise toxic to our wet pets. Mechanical filtration collects undissolved organic materials where we can physically remove it more easily. Chemical filtration,if used, collects dissolved materials for removal similarly. Water changes remove buildup of undesirable dissolved materials (both organic and inorganic) on a broad scale - in exactly the percentage equal to the percentage changed. They also replace materials in the water which have been used up or depleted. There are many minerals that are depleted from tank water over time as a fully normal biological process, and we do need to replenish those routinely. Equally, we must remove from the wet pet's environment those things which we have no tests to measure - dissolved organics are the bggest contribution to that unreadable pollution, but some inorganics also are part of that. Filtration and water changes combined are required equally. The best possible filtration, even massive over-filtration cannot remove everything undesirable from the water - many things are untouched, or are themselves product of filtration biology. Similarly, water changes alone are impractical for control of toxic materials either short or long-term all on its own.

Both biological and mechanical filtration are needed in routine operation, and regular water changes are equally needed. Our tanks have many times the bioload (live biomass) of natural waters, plus we add foods to the tank routinely to maintain that biomass. So we need both on a continuous or regular basis.

HTH (Hope that helps)