Large Tank Water Changes

lwhillman

New member
To do water changes on my 1200g reef I now drain the display tank down about 15% and then refill from a Vat. It works ... but prevents me from putting coral in the top portion of the display tank.

There's gotta be a better way.

Any Suggestions??
 
Automatic Water Changes.. Check out the Genesis Renew. It does 1 gallon at a time and up to 99 gallons a day or up to 99 gallons in one continuous batch. That's what I use and it's the best water change solution on the market.
 
Automatic Water Changes.. Check out the Genesis Renew. It does 1 gallon at a time and up to 99 gallons a day or up to 99 gallons in one continuous batch. That's what I use and it's the best water change solution on the market.

^^^ This, best purchase I made for my large tank setup. Look up saltwater mixing stations on here and build one of those and you are ready to go. Well worth the investment IMO.
 
Ah but my sump is only about 50 gallons .. and I'd like to do 200 gallon changes as thats a full bucket of salt (easy to mix) and for the larger dilution.

Then I repeat what slief said above, Genesis renew will work perfect for your small sump. It replaces 1 gallon of water at a time

I just installed a Genesis Renew about 2 weeks ago on our 700g total volume system and we are loving it. Cannot even believe we didn't invest in one of these sooner.

How much water do you change per month?
 
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Then I repeat what slief said above, Genesis renew will work perfect for your small sump. It replaces 1 gallon of water at a time

I just installed a Genesis Renew about 2 weeks ago on our 700g total volume system and we are loving it. Cannot even believe we didn't invest in one of these sooner.

How much water do you change per month?



I have a reef genesis as well based on suggestions from here. Water changes have never been easier. I cant even imagine how to do it any other way. I also have their Storm top off. Works like a charm.

both are awesome, well thought out devices.
 
I agree daily/auto water changes are easy ... but big changes are much more effective.

For Example, a single 200 gallon change (in my 1200 gallon tank) reduces Nitrates and other impurities by 16.7%. Twenty 10 gallon changes only reduce 7.9% ... about half as effective.

I'm hoping there's a way to keep the effectiveness high ... and populate the top of my tank!
 
How long is the water level down? Should be able to find lots of things that will tolerate being out of water for short periods.
 
I agree daily/auto water changes are easy ... but big changes are much more effective.

For Example, a single 200 gallon change (in my 1200 gallon tank) reduces Nitrates and other impurities by 16.7%. Twenty 10 gallon changes only reduce 7.9% ... about half as effective.

I'm hoping there's a way to keep the effectiveness high ... and populate the top of my tank!

I normally do two 200 gallon changes a month. Daily/Auto changes solve the problem ... but are much less effective in reducing Nitrates, etc.

What you are missing is the consistency that the automatic water changes bring. While it is true that a big water change is more effective if you are having issues that you need to address, the idea is that the consistency of the daily water changes will keep your water consistently cleaner and more nutrient free than larger weekly or monthly water changes. Thus, the effectiveness of the daily automatic water changes are more effective in the long term than your larger monthly water changes.

With the larger weekly or bi-weekly or month water changes, the water quality diminishes between the water changes where as with the daily water changes, the quality of the water is consistently better. My system is 650 gallons and I have a pretty large population of heavily fed fish. I have had this tank for over 20 years. I used to do the large water changes and was always fighting water quality and nitrates. Since switching to the daily automated water changes, my water quality is consistently better and I use less water over all. My nitrates are now pretty much undetectable and I only change 5 gallons a day. If I want to increase that water change amount, it's as simple as a push of a button. Since switching to the automatic water changes 6 years ago, my tank infinitely healthier, my corals are thriving more so than they have in the last 20 years despite my excessive feeding and my fish population is larger than it ever has been. Trust me when I tell you, daily water changes is by far better for the tank than larger weekly or monthly water changes.
 
Hi Iwhill. I do the same as you , but I am assuming you have a sump? If you do take the water from the main display. Pump the water back in out of your sump and then fill your sump up. I do this and corals are out of the water for about 5 minutes max.
 
Hi Iwhill. I do the same as you , but I am assuming you have a sump? If you do take the water from the main display. Pump the water back in out of your sump and then fill your sump up. I do this and corals are out of the water for about 5 minutes max.

How do the corals take to being out of water for +/- 5 minutes?
 
How long is the water level down? Should be able to find lots of things that will tolerate being out of water for short periods.

Yeah, this. You really should be fine with some exposure, usually they'll hang onto some water anyways so should be fine, if you have 400 watt halides though I'd turn them off though

My issue with any auto water change is I like to siphon crud off the bottom, orin places there might be "dead spots"
 
Yeah, this. You really should be fine with some exposure, usually they'll hang onto some water anyways so should be fine, if you have 400 watt halides though I'd turn them off though

My issue with any auto water change is I like to siphon crud off the bottom, or in places there might be "dead spots"

Auto water changing sound like its PART of the solution ... but not a replacement for Manual Changes/Cleaning/Etc.
 
This is partly why I'm hesitant to get a very large tank. Where do you buy your salt? 200 gallon water changes @$40 each?

Then I wonder, wouldn't changing water at a larger volume at a time be more effective than continuous water changes where you are in theory draining some of the fresh water that you just incorporated back out? Ie it seems like it would be better to do twice daily 10 gallon changes or something rather than hourly 1 gallon changes
 
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