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How often do you change out water?


Pygmy Octopus
Mar 11, 2005
How often do you change the water out in your tanks. Mine is a 42 gallon with a bimac, and I've been told both ways one says very rarely and the other is week to months. Also what do you do for storing your clams. I do not want to set up another aquarium just for them, and the shrimp thing is getting old. P.S. nobody sells reverse osmosis water near me.
Hi Leigh and welcome to TONMO.com! :welcome:

I think the recommended amount is about 10% a week, or 20% every couple of weeks. Watch your water parameters, too - water changes are one of the ways to lower nitrates.

We've located large jugs of R/O water at Walmart's, Culligen's, Whole Foods, and many other stores. It's purified drinking water... just look at the label carefully, it will say "reverse osmosis" A five gallon jug of this R/O water would make enough saltwater for a 12% water change. You can also use distilled water as a basis for making salt water. I use distilled water for my top off water as the water level evaporates.

You could put the clams in a little net breeding container at the top of your tank - remove the any that are dead. What is this "shrimp thing" that is getting old?

Welcome to Tonmo! I can sympathize with the shrimp thing, I ate almost a pound last night, and my heartburn is killing me (but they were soooo good...hot !)
Nancy is spot-on about the water changes...the more frequent they are, the better !
Another great place to purchase r/o water is Home Depot or Lowe's...they sell it in 3.5 and 5 gallon jugs. It is too bad your lfs won't sell water though...ours gives it away to long time customers.
Be sure to enter your tank into the database !
I have 3 aquariums a 75 gallon reeftank, a 12 gallon nanocube and a 58 gallon with my bimac. I do water changes every other week. I bought several of the 5 gallon red gasoline containers from home depot and go up to the lfs and get them filled with salt water. I do 10 gallon's on my 58, 15 gallon's on my 75 and 2 gallon's on my nano tank. Since I've started doing this I have noticed that all my tanks have been doing much better, exspecialy my reef tank,the xenia and some of the other corals have just taken off and are pretty much out of control. just about once a month I go in and start fraging my corals just so they don't take over my tank.

Can always work it out.....

If you log your nitrate results you can work out a good water change regime for your tank. I believe you can keep anything alive in a tank with proper water changes.
Besides with every new water change my live rock comes alive! Have lots of filter feeders and those guys love fresh water.
Most of my tanks get a 25% change every single week. Just makes it easier to know when to stop the gravel vac...... and seems to work alright. If I am feeling lazy I test the water...... always nice to know if you CAN afford to put it off.

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