Water change

[Den_Pid]

Hi guys, so the question here is do I have to change the water of a 900 liters aquarium. My local pet store, where I am going to purchase the tank says that if it has a powerful skimmer and a nice established sump system, water changes are not needed. But I think that once a week I should do a 10-15% water change. Or when the parameters spike. So… Please for advice.

 

[dwair]

Thats a loaded question to ask. You are going to get alot of differing opinions on this subject. Its a very widely debated topic that has merits to both sides.

I'm going to try to be unbiased here and give you information from both sides without showing you my opinion as ultimately its your tank and you need to decide whats best for you and your tank (maintenance uptime, etc).

Benefits of doing water changes are immense, you reduce nutrient levels in the tank, remove possible organics on sandbed and off rocks, any algae you can scoop off rocks etc. You also replenish trace elements that we can't test for without an ICP test and replenish the big 3 as well, Alk, Calc, Mag. Now the issue is, if you don't test your new saltwater before adding, it could cause a big swing in your tank. Most people mix their new saltwater and then adjust the levels in their mixing container to what it is at in the tank to not cause a swing. Example is your tank is at 7.5 DKH and your salt mix is 7.0 DKH, you can add a little alk to it and get it up to 7.5 DKH and it matches your tank then.

Benefits of Not doing water changes are you don't have to have the headache of doing it for starters lol. But that means you have to makeup for it by dosing. To be clear even if you do water changes on a regular basis you STILL might have to dose according to your tank needs, your tank could be consuming more than what your water change will solve. Example if you are consuming 2DKH per day and your water change only covers 1 DKH, you'd still need to dose.

But most people that don't do water changes at all are dosing trace elements and 2 part everyday. 2 part being Alk and Calc and Mag when it needs it. You also won't get out any ugly algae without manual removal that isn't by water change. And you really have to depend on your CUC (Clean up Crew) to remove anything from your sand bed as you aren't vaccuming it during a water change.



TLDR - Both are viable options and both have been proven successfully over the years by MANY reefers on both sides of the camp. Just know the pros and cons of each and base that off of your own time commitment to the tank.

I should also mention you can automate water changes as well. Something to think about.

Good luck!

 

[BlennyTime]

You should plan on doing water changes, definitely in the beginning and possibly indefinitely. You may get to the point where the tank is established and stable enough to eliminate them (and many people do), but that will come later and depend on a variety of factors. Testing the water as the tank grows will let you know if you are getting to that point.

if you plan to have coral, you’ll need to dose supplements to replace what the coral are consuming.