mixing large amounts of water

How big is your tank? I don't think you'd have to do a 50% all at once! Why not spread it out and do like 4 20% changes over a few days?

 

its a 40 breeder

 

i just bought an 18 gallon tote from walmart for like $8 i think! I wouldn't go through all that expense for 2 water changes! i'd get that, a cheap heater and a cheap pump! ya need them anyways, and i'd get 2 totes(1 for the RODI water you can store for top offs and water changes, and 1 for mixing!) You could easily mix up 15 gallons, it's not 50% but close! good luck, i had the same prob, i was just using RO water and fighting cyano, within a month of using a RODI and prob 5 10-15% water changes i noticed a HUGE difference!

 

Agreed. In fact, I'll bet you'll see a change after the first 20%.

 

Mixing Saltwater - YouTube

 

This is exactly how I mix my water right now, I just do it in a 5-gallon bucket instead of a big brute can. I normally do a 10% change every other week and 4 gallons is 10% of 40 gallons so the 5 gallon bucket works perfectly

 

good deal, Now ya just need to start using the right water and alot of your problems should slowly go away!

 

I've done one water change with the RO/DI water and using it to top off and already I can see the difference. My war coral which hasn't grown much over the last 2-3 months is now growing like crazy.

 

cool, get mine to grow for me! She's groing, just not that quick!

 

+1 on those that suggested a series of smaller water changes will be just as effective as 1 larger one

doing 5 gallons in a 40 is approximately a 13% water change , thus 87% old water and 13% new
week later another 5 gallon water change will mean approx 24% water will be new and 76% old
by week 3 = 33% new water and 67% old - week 4 = 42% is new and 58% is old

if your using and have been using GFO and Carbon in your set up, you have been reducing the problem anyway ( although not as fast as the tap water has been creating it)

if you slowly improve the source water, you avoid any potential shocks to the inhabitants and save yourself some costs in the mean time

if you do want to perform larger changes with your existing equipment you could do as follows

mix 1 x 5 gallon bucket, with heater and pump
once it is mixed, fully dissolved, remove pump and heater and put a lid on it (empty large salt buckets are great for this as the lids fit air tight)
mix up the next bucket, and repeat until all buckets are mixed

once mixed , if they are sealed tight they can be stored for long periods ( just like the pre mixed saltwater we can buy , is held in storage )

keep them in a warm location until ready to use and you could have 20 gallons of saltwater pre mixed, that might need a few minutes agitation and possibly heating prior to use

Steve