Water Changes & Wet Dry's

[aquarius 1]

I've come to a crossroads in the routine of my tank maintenance and I was wondering what everyone's opinion was on the frecuency of water changes. High nitrates in my 75 gallon have been a consistent problem... The tank is filtered by a Fluval 303 Canister and two DIY wet dry's composed of bioballs, carbon, and filter floss. I've heard that more frequent water changes help to keep nitrates down, but do these frecuent water changes also negatively impact the tank? Is changing 6 gallons of water a week a bad idea? I've also head of changing 10-20% of the water once a month...is this a better way to go? Is changing all this water bad for the tank chemisty? If you keep changing all this water does the bacteria have ample time to break it down? In addition to water changes how often should the wet dry filter floss be rinsed and cleaned? I"ve been rinsing the floss twice a week because after a couple days they become clogged with debis. Is this too often? Finally, what if I just let the tank go....let nature take it's course, hold off on water changes and frecuent cleanings? Will this hurt the tank even more? I know there's a lot of questions but thank you for your time.

 

[thomas712]

Originally posted by Aquarius 1
I"ve been rinsing the floss twice a week because after a couple days they become clogged with debis. Is this too often?
Just my opinion but I think this may be the krux of your problem, not that you rinse it twice a week but that you HAVE to rinse it twice a week. This suggests that you are overfeeding the tank and your livestock is overproducing waste, thus the high nitrates. Also that you are reusing? the filter floss. I personally change mine once every couple of weeks and toss out the old. ONce it changes from white to tan, or gets clogged, replace it.
Cut back on your feedings.
Examin how much you feed and how often also what you feed.
What type of substrate and if sand how deep?
The fluval could also be a source of the problem.
Thomas

 

[cgr]

I do not claim to be an expert but like you, I have often asked my self the same questions. I switched from cc to dsb, 5+" and it has made a dramatic difference in my tank. I too have the same filter with bioballs, carbon and filter material. I take the filter floss once every ten days or so and clean it very well. After two cleanings I usually throw it away.
120 Gal FOWLR
1 Yellow tang
1 Blue tang
1 Sailfin tang
3 chromis
1 cleaner wrass
1 tomato clown
1 sleeper gobie
1 scooter blenny
1 bicolor blenny
1 coral banded shrimp
emerald crabs, snails, blue and scarlet leg hermits
Wet/Dry filter w bioballs
5+” DSB
Ammonia 0, Nitrites 0, Nitrates undetectable,
PH 8.2, Salinity 1.024
I also used to overfeed, usually twice a day. I now feed my fish once, about two hours before the lights go out for the night. My tank is sparkling clean, nitrates are undetectable and I have not lost a fish in over a year. It is not always easy to fight the temptation to feed since they always seem hungry but in my opinion you'll get better results.

 

[sebae0]

i have also thought the same thing but in reality i think that wet dry's are so effiecient that it produces nitrates faster than it can be broken down thru the nitrogen cycle.
remove the bio balls and use it for circulation and put in a dsb and a fuge if possible and your nitrate problems will start to go away. jmo

 

[aquarius 1]

I'm using crushed coral as a substrate and I have realized that I do overfeed. Thomas, what is your reasoning behind having the Fluval be the problem? Also, when I cut down on the number and amount of feedings, should I continue with water changes or just let the tank take it's course (or am I looking at a death wish)? If so how much and how often?

 

[cgr]

I do a 20% water change every month but have been advised that 5% weekly might be more effective and better for my tank. I must admit that there have been times when I have gone two months and have not had any problems.

 

[thomas712]

Depending on your routine cleaning of the canister filter it collects the fish waste and uneaten food, with it being traped in there this can easily lead to a nitrate problem. Nothing in the canister can help eliminate nitrates. They are best to polish the water or use to run polyfilters, phosphate sponges, carbon, which can help to trap the particles that cause nitrates, but if left there then they will only return to the water colum unless removed and cleaned.
Now if you were cleaning the filter floss twice a week due to it becoming clogged then it stands to reason that your canister filter would also need to be cleaned. It can be one of the reasons why you have high nitrates. Clean that canister out and replace any fresh carbon.
I would continue with the water changes and vaccum that crushed coral out as much as possible.
If you do not have one then get a protien skimmer, in sump modles work best but hang on can be a plus when you have crushed coral.
Thomas

 

[offshore80]

I too have heard that a canister is nothing but a Nitrate factory and to stay away from CC. they both produce nitrates at a high rate. IMO the water changes are whats saving your tank now. From what I've read I would disconnect the canister completly and then if you still have a nitrate problem try a hang on the back fuge with some nitrate hungry plants.

 

[jrittz]

This may be along the same lines and hope we can get an answer in this thread...It's in direct response to the questions and responses in this thread.
I have "heard" that taking the water from the bottom of the tank is good because all of the water from the top of the tank is the best quality water for the fish/tank. Taking water from the bottom will help to eliminate a lot of the impurities on the bottom of the tank where it is said to accumulate. Then I have also "heard" that taking water from the bottom of the tank and also cleaning out the CC will suck out beneficial bacteria needed for the tank to maintain it's eco-system properly. Can anybody please answer this with not a "I heard from so-and-so" but with true proven fact? Yes I encourage response whether you know this answer or not but hopefully we can get down to the bottom of these two myths and prove or disprove them. Heck, they both may be true and then it becomes a dilema.
Jrittz

 

[thomas712]

Jrittz - Sorry no facts to give you only my opinion.
One of the reasons that overflows were invented was because people found that DOC's or dissolved orgaincs and oils rise to the surface and therefore this is the best place to collect them. Now to me that just makes some sence but doesn't disprove any pollutants in the middle or bottom of the tank either but I feel of course there would be as in the crushed coral senario.
Now in our reef tanks or what have you, many of us talk about turnover rates, if this turnover rate is sufficiant then much of the DOCs, oils and other pollutants would be kept in solution more evenly without collecting in one specific area of the tank, instead of at the surface where much of the dissolved stuff seems to. This would mean the whole water colum.
Now logic might tell us that the lighter dissolved stuff would collect at the top and the heavy pollutants would go to the bottom until they in turn become dissolved, if possable, and also go toward the surface. It might be a question that we might ask some of our more unfortunate reefers that suffered from the black out to ask if they noticed without water current if they had more film on the top of their tanks, and other stuff on the bottom that may have collected.
So I think that the key to the pollutants in the tank can be helped by keeping adiquite turnover rates to keep them in solution to be removed by what ever form of filtration that you have on an even basis.
In a crushed coral system I do not believe that you will be able to stop the heavy pollutants that will be traped by the cc, but I do believe that the will eventually become dissolved and then released into the water colum, either middle or surface, it would all be a concern.
Hope some of that makes sence.
Thomas

 

[thomas712]

Now in the case of a water change in a system that had an sufficiant turnover rate to keep the pollution in solution then I do not think it would matter where you syphon the water from, top, middle or bottom. However in the case of a water change in a crushed coral substrate I would most definatly go for the bottom syphoning the crushed coral.
As to the bacteria question. If all you had was a fish only and no other form of filtration you would still have no choice but to vaccum the cc to keep it from polluting your water. Its like when many of us had freshwater fish or were just using saddle filters to filter our tank, sooner or later we had to rinse or replace the filter pads, knowing that we will be upsetting the bacteria bed. Then they came out with the sponge behind the filter pad or the bio wheel that helped to keep the bacteria bed. With the Crushed coral you could still vaccum only 1/2 or 1/3 each time you did a water change and not upset the system to greatly. The need to clean that CC out weights the threat of disrupting the bacteria bed. Our systems can get over a mini spike.
Thats enough about that, all I can say is thank GOD there are other forms of filtration as opposed to using crushed coral.
Thomas

 

[offshore80]

Trial and error baby... You got a try something. I was steered away from the canister filters for that very reason by several shop owners when I was shopping for a filter for my saltwater tank. Hmm, maybe that's why I don't have a nitrate problem. As far as the crushed coral... Same deal there. I was told to stay away from that from this site by several members. hmm, maybe that's why I don't have a nitrate problem. Unless someone out there has done a double blind experiment that's all you got is what you've heard or experienced for yourself.
*** hope you don't mind a little edit here, no need for that type of wording or baiting*** Thomas

 

[jrittz]

Thomas712:
Thanks for the timely response and what you've said totally makes sense. I'll definately keep that in mind while doing my regular water changes. It's very difficult sometimes to come up with hard facts in this hobby so in most cases an opinion can be looked upon as fact which most if not all of what you've said can and will be taken.
Thanks,
Jrittz