Thoughts on methods of eliminating water changes ?

[justingraham]

Maybe BRS can conduct a test running a sizable skimmer on RODI tank for a period of time and run an ICP/triton test on it. It should give us an idea the amount of contaminant going into our tank via skimmer @Ryanbrs please consider

I don't think Skimmer's skim regular water.

 

[Big_Macc]

Just my 2 cents. I agree that the main reason we partial water is to remove the suspended waste. Our filters, (skimmers, media, etc..) do most of that, but the waste that collects in the substrate and rock is what usually causes the problems. Right now Im trying to reduce water changes by flushing the substrate and rock with a powerhead every two weeks and letting the carbon and skimmer take care of suspended stuff. I just top off the tank for evaporation.

 

[Donovan Joannes]

I don't think Skimmer's skim regular water.

Agreed, maybe air scrubbing is more appropriate terms to use for this test.

 

[Big_Macc]

Just my 2 cents. I agree that the main reason we partial water is to remove the suspended waste. Our filters, (skimmers, media, etc..) do most of that, but the waste that collects in the substrate and rock is what usually causes the problems. Right now Im trying to reduce water changes by flushing the substrate and rock with a powerhead every two weeks and letting the carbon and skimmer take care of suspended stuff. I just top off the tank for evaporation.

The 'water' itself never goes bad, just whats in it.

 

[scott cheek]

Ok here is my tank. It is way overloaded but it's stable just finished water test.
Ph 8.3
A 0
Nitrite 0
Nitrate 10
Phosphate.025
C 440-460 hard to read
35+40 fish
145
Sulphur reactor
CO2 scrubber
GFO reactor
Bio pellet reactor
Carbon brs twin
I am about 8 months in on this setup trying to get it ready for SPS.

 

[Scott.h]

First, let me say that I'm approaching this from an average hobbyists point of view or capabilities, not just experienced people.

There are so many variables in the tank. Some people don't like a lot if rock, thus less bacterial population (if they're not using a marine pure or something similar).

Of course beneficial bacteria cleans, but the majority of bacteria is aerobic bacteria which just handles ammonia and nitrites.

You have to find a way for constant denitrification in your tank. How would you accomplish this without a dsb, or on bare bottom tanks? Most coral tanks have a lot of flow, so most of the rock work is getting oxygenated.

Yes you can add bacteria, but is there just a denitrifying bacteria? No. They're all pretty much chemical band aids for the main cause. Then you have people that constantly add too much and have bacterial blooms.

I have 2 big jars of CaribSea Rubble Zone in my sump. I drilled holes in the container so water could pass through and put it in a low flow area. That's not even helping all that much for denitrification.

Again, maybe this is a topic for only advanced hobbyists, but I try to look at things the average person would go about them. Most people don't even understand the nitrogen cycle. They just know you're supposed to replace X amount of water every so often.

There is more going on in a tank with the bacteria then most realize. I have no sand whatsoever, an average amount of rock, and a fuge with a small amount of macro (on purpose). The denitrifying is happening somewhere. I'm adding N daily with a dosing pump. On top of that I'm adding .2 ml liquid phosphate daily, and haven't used gfo in about 8 months. Ive never carbon dosed this tank. I've eliminated activated carbon, sock filters, and even more.. for the last few weeks I've added every bit of my skimmate back into the water 2x a day. (Skimmer keeps my ph slightly higher). My tank is absorbing more, as my dosing has increased consistently since I've stopped water changes. Like it forced my rocks to mature more. Per my sig I haven't removed one drop of water in about two months. Only reason I did two months ago was from elevated aluminum and the dang marine pure blocks. Otherwise I wouldn't have then. N .75 , P .009 read today.

Unfortunately my first tank, still running, I've always struggled with keeping things in check, hence the filtration focus on this system.

 

[scott cheek]

 

[Scott.h]

Apart from removing nastiness, skimmer does help in oxygenation as well. Ever heard of Air Pollution Index?. In urban and city area with windows wide open, impurities introduction is unavoidable. What about air freshener, scented candles, perfumes, cooking fumes etc?. I think you should get the idea by now.

heh, yeah stay away from the glade oil plug ins. The wife added a few of those a few years ago and jacked up a few corals instantly. Seems like it actually killed a few before I figured it out.

 

[Donovan Joannes]

heh, yeah stay away from the glade oil plug ins. The wife added a few of those a few years ago and jacked up a few corals instantly. Seems like it actually killed a few before I figured it out.

Exactly. Sometime we forget that skimmer can contaminate our tank if the air being pulled contains impurities, substances or things that is bad for our hobby.

 

[Scott.h]

Exactly. Sometime we forget that skimmer can contaminate our tank if the air being pulled contains impurities, substances or things that is bad for our hobby.

Yep. Oh yeah.. forgot to turn off the skimmer once (plumbed outside) before fertilizing. Caused issues. Adam at battlecorals had a problem with neighbors and mothballs too.

 

[Steve Fast]

First my apologies for not taking the time to read the entire thread... So a week or two ago I ran the math on this. For removal of bad stuff or addition of good stuff, water changes converge to a steady state depending on how much you do how often. It will never remove all the bad stuff or keep the good stuff at the levels of a fresh mix of seawater. If you want to do either of these you will need another solution: dosing for trace and other techniques for removal of nitrate/phosphate and other bad organics. I'm curious how very large systems (> 500 gallons) and/or public aquariums handle these issues. Water changes for them would be very expensive and impractical.

 

[AutumnSky]

Enjoying this volley of ideas, comments, speculation and common sense seasoned with experience.

With my small /nano tanks and in some ways affects me more (small amount of water so more chance for disaster for a small problem), but then less, as a small bioload of inverts and fish, as doing a pwc on a nano tank takes a few minutes and low cost.

But I have though about this too, as when I test I can have great water parameters, but even letting the pwc schedule get lax, know it has been awhile, wonder if it really is necessary. Obviously with a really large tank set up it would be more useful to make a water change only when required, for all of the reasons mentioned.

My experience with SW has been limited in 35G and less, and I want to say I appreciate all of the information and thoughts you guys are sharing. Especially as sometime I might want to get a bigger tank and be able to look here for historic experiences. Thank you.

 

[Fercho]

I believe is possible but only in a fully mature reef that has a conciderable amount of beneficial bacteria and coral that will consume most of the nutrients to outcompete any bad algae outbreak.
Also, this will require to keep up with cleaning tank and sump as soon as detritus builds up to avoid nitrate and phosphate spikes.

 

[reefk]

Following, interesting topic.

 

[Mark Gray]

You mean a bacterial soup - because it will be that in the water rather soon - in a matter of hours or days. What you think is waste in the gravel or in the filter is in reality just bacteria populations and some organic matter that will take some days before it’s broken down. And its food for snails, sea cucumbers, hermits, worms, sand sea stars and other critters. And if you stir it up – your corals and other filter feeders get bacterial plankton. It’s no waste – it’s a resource if you know how to use it.

No - but to drink my pee is probably the only thing that I have not done with pee - yet - However there is an India philosophy school that says that you should drink your morning pee in order to stay calm the rest of the day

Sincerely Lasse

Interesting but I guess I will keep my blood pressure high lol

 

[Kayvon]

Can corals derive trace elements from feedings rather than supplementing elements into the water column?

 

[Bruce Burnett]

My 300 gallon system has been setup 23 months. Bare Bottom, oversized skimmer, not overly stocked, lots of rock, calcium reactor, no water changes. Phosphates zero on Hanna, nitrates barely change color on Salifert.

 

[|sCRIBe|]

I use to do ~10% water changes and it seemed to cause instability and some corals would look terrible or die quickly after. I havnt done a water change in months and my tank is at its best. I don't vacuum or clean the sand either. Everything is bright, growing and healthy. Mixed tank of lps and few sps.

 

[Donovan Joannes]

My current tank... cross finger it will continue to grow and color up a bit more without doing WC. I am keeping some money so that I can buy nicer coral from the web

 

[dankreef]

I have a 6 month old tank packed with sps and I haven't only done a little siphoning sand a few times . I find that sps soak up nitrate and p04. I don't run a skimmer either. If my p goes up a little I just back off feeding or run carbon for half a day or so. CA reactor for all the trace and stable dkh calcium mag . Sps are looking super so far .