when does a water change become irrelevant

[Proteus]

Originally Posted by BlueTang<3

Not sure how many of you guys monitor orp, I can tell tho from that level when to do a water change it hovers around 340 about a day after a water change, naw is around 250 but once it recovers I watch it and when it starts to fall again I do a waterchange. I can notice if I leave it drop a little more things start going a little funny.

This is something that I've consider monitoring. But thought irrelevant. Ypu could control your orp to remedy this problem though I would wonder the cost vs wc

[Aquattro]

Originally Posted by Proteus

Ypu could control your orp to remedy this problem though I would wonder the cost vs wc

I would then argue that controlling ORP with external influences is simply masking an underlying issue (to a degree). Again, it may extend the window, but not make it irrelevant.

[Magickiwi]

I monitor ORP because I run ozone and I do notice that after a water change my ORP reading hits the floor. I keep my tank around 325-350 between water changes but after a change it goes down into the 1xx range. It will take the better part of a week to get it back up. What does that mean in terms of the need or benefit of a WC? I dunno, but I'm not stopping my bi-weekly change to find out. I will let the braver people experiment with their tanks

Water clarity does seem better when my tank ORP is in the 350 range as does the vitality of the fish. Similarly my inverts etc. all seem to love the higher ORP readings.

[Proteus]

Originally Posted by Aquattro

I would then argue that controlling ORP with external influences is simply masking an underlying issue (to a degree). Again, it may extend the window, but not make it irrelevant.

Are you masking or remedying. If after a wc the orp goes down that's a imbalance.
My hottub for example users ozone to oxidize organics which means I don't have the chemical additives to remedy and also prolongs the time between cleaning

Truth told we would need a chemist to do a proper analysis of a tank before and after a wc to really find out the true story.

[Aquattro]

Originally Posted by kien

This is a very good question and I'm curious myself. We are all trained to believe that a water change is the bees knees, but if you're running on balling, have a really good skimmer and run carbon to take out dissolved organics, then is it ?

I think that's a reasonable question only if we assume a close to 100% efficiency in our methods of removing and adding things. But I'm sure for every cup of crap my skimmer pulls, it leaves a cup. Carbon? Is it removing everything bad? For how long? What is dosing/balling adding that we don't account for? Is it harmful if it builds too high? In my mind, all these things simple prolong how long you can go between changes. For my comfort level, that's 2 weeks. Maybe I can go longer, maybe not. There's really no way to tell. So based on the effort it takes and the cost of salt and water, I've chosen a schedule that works for me, my wallet and my tank. As I said earlier, using the same equipment across multiple tanks, this one, with the more frequent changes, is by far my most successful tank. YMMV

[kien]

Originally Posted by Aquattro

I think that's a reasonable question only if we assume a close to 100% efficiency in our methods of removing and adding things. But I'm sure for every cup of crap my skimmer pulls, it leaves a cup. Carbon? Is it removing everything bad? For how long? What is dosing/balling adding that we don't account for? Is it harmful if it builds too high? In my mind, all these things simple prolong how long you can go between changes. For my comfort level, that's 2 weeks. Maybe I can go longer, maybe not. There's really no way to tell. So based on the effort it takes and the cost of salt and water, I've chosen a schedule that works for me, my wallet and my tank. As I said earlier, using the same equipment across multiple tanks, this one, with the more frequent changes, is by far my most successful tank. YMMV

I do have an ORP probe and it does fluctuate up and down. I never really payed much attention to it because it didn't move all that much. Even when I'D go a month without a water change I never noticed a significant change.

We all know that every tank is different so ya, your mileage will definitley vary. What's interesting is that there are people who do very little water change and seem to get by just fine. The water change schedule is all over the map.

I'm kinda in the same boat as you. I'm on a two week schedule that seems to work best for me (and my wallet too). I used to do weekly but can't accommodate that anymore. The tank doesn't seem to care.

[don.ald]

My system is about 100g vol.
No probes, carbon, or pellets no gfo
Lots of blue clove coral though LOL (must be a great filter)
I do 5 gal change twice weekly. That's what works for this system and for me.

[FishyFishy!]

Does anyone recall the DSR (Dutch synthetic reefing) method? There is a lot of controversy surrounding it, but it does make a lot of sense when you look at it. Simply replacing all elements that diminish over time, and zero water changes. Glenns 300 gallon tank on reef central is outstanding, and he hasn't done a water change for maintenance in years (not to mention he dosn't have a functioning skimmer, and very little equipment other than dosers). A very neat theory, but theres no way that I could keep up with all the testing all the time. I think regular water changes are going to be the key for me.

When I look back at it, all of my successful tanks were those that had regular water changes. All the ones that I neglected to do water changes on, had zero abilities to grow and keep even the simplest of corals.

[sphelps]

The Zeovit method requires water changes, I believe the guide states 10% per week to maintain the element balance. As far as bailing goes the idea is to increase stability between water changes, pretty sure it's been stated many times it doesn't replace or reduce the need for them. The way I see it is you're adding elements to replenish those being used thus promoting stability but at the same time there's pretty much zero chance it's being all replaced at same ratio it's being used. Water changes will maintain the balance by removing and replacing, cutting back on them would reduce overall stability thus defeating the purpose of the bailing in the first place. So as far I'm concerned the addition methods you've employed are additions to reduce nutrients and promote stability but have no relation to making water changes irrelevant.