water changes

tanyamikephil

New member
Im battling high nitrate levels (40ppm now). I have been doing a 20% water change every other week in my 55g tank.

It is helping maintain the level but not reduce it so I wanted to ask how often would be to much if I started to do the water changes more frequently?

Also are there any products that anyone has used that actually worked for this issue?
 
Many use vinegar or vodka dosing or biopellet reactors or sulfur reactors or macro algae (cheato) in a sump or reactor to reduce nitrates..
I've been using vinegar with very good results in past tanks.

You can do daily water changes if you want.. or a few larger ones until it lowers.. just make sure you are matching the salinity to keep it stable..
Theoretically a 50% water change should drop your nitrates by 50%..

Fish and soft/leather corals can easily tolerate higher nitrate levels so 40 isn't "horrible" but most try to keep it at 10 or below..
 
If salinity, temp, and alk are the same in the new water, you can make about as big of a change as you want. Frequency won't cause any issues either. I would do 20% a week instead, until the levels come down.

Export of nitrates can be done with macroalgae, turf scrubbers, deep sand beds. Carbon dosing with vodka, acetate, etc can work as well, but do your research first.

Edit: mgyvr types faster than me.
 
Many use vinegar or vodka dosing or biopellet reactors or sulfur reactors or macro algae (cheato) in a sump or reactor to reduce nitrates..
I've been using vinegar with very good results in past tanks.

You can do daily water changes if you want.. or a few larger ones until it lowers.. just make sure you are matching the salinity to keep it stable..
Theoretically a 50% water change should drop your nitrates by 50%..

Fish and soft/leather corals can easily tolerate higher nitrate levels so 40 isn't "horrible" but most try to keep it at 10 or below..

We also have hard corals, anemones, shrimp, and zoanthids"¦will it harm them?
 
Would this be the reason why my hard corals are fading?

how old is your tank? what does the cleaning entail? how many times to do you feed? what filtration/fuge are you running? How many fish ?
While vodka/vineger dosing does indeed work these are methods reserved for aged tank's if you are dosing these in a young tank we need to look closely at what you are doing get a better idea of what's really happening
 
how old is your tank? what does the cleaning entail? how many times to do you feed? what filtration/fuge are you running? How many fish ?
While vodka/vineger dosing does indeed work these are methods reserved for aged tank's if you are dosing these in a young tank we need to look closely at what you are doing get a better idea of what's really happening

Our 55g tank is 6 months old. i feed the fish once a day for which i take my time so not to over feed. We have a protein skimmer and filter hanging on the back. we also have an RO/DI system for the water. We have 10 fish, 2 shrimp and 2 anemones. We also have zoanthids, hard corals both are just frags, and some other things i can't remember the names of.
 
Our 55g tank is 6 months old. i feed the fish once a day for which i take my time so not to over feed. We have a protein skimmer and filter hanging on the back. we also have an RO/DI system for the water. We have 10 fish, 2 shrimp and 2 anemones. We also have zoanthids, hard corals both are just frags, and some other things i can't remember the names of.

PS"¦I really didn't want to mess with vodka dosing anyway.
 
Our 55g tank is 6 months old. i feed the fish once a day for which i take my time so not to over feed. We have a protein skimmer and filter hanging on the back. we also have an RO/DI system for the water. We have 10 fish, 2 shrimp and 2 anemones. We also have zoanthids, hard corals both are just frags, and some other things i can't remember the names of.
that is quite the bioload for a 6 month old tank, nem's depending on the size put out quite the bioload believe it or not. do you wet skim at all? how often do you turkey baste(blow) the rock's? these small things when left unchecked even dirty filter sponges can add up over time give these a try I do think stepping up the w/c weekly to say 15% would see a vast improvement with no fuge and the tank being inside it's first year you're not doing that bad with the bioload2nitrate. step up w/c and let the tank slowly adjust to the load you should be fine xD
 
With a high bioload in a new tank, it's probable that your bio filter (bacterial colonies) are still maturing and building, especially the anerobic species that transfer nitrates into nitrogen gas which leaves the water. The bio filter will probably grow some more as the tank matures. Make sure you have plenty of surface area aka as sand and enough good live rock. And siphon out detritus & uneaten food, wet skim, keep up on the water changes and assess if perhaps you're over feeding.
 
Since you want to keep corals, you might consider re-homing a couple fish so you can reduce feeding until things come into balance and you can keep your levels where you want them. 40 ppm nitrate and enough light for hard corals is asking for an algae nightmare, and it can come on quickly.
 
Just wanted to say thank you for all the input and i know this may seem like a dumb question to some of you but what does wet skim mean?
 
Our 55g tank is 6 months old. i feed the fish once a day for which i take my time so not to over feed. We have a protein skimmer and filter hanging on the back. we also have an RO/DI system for the water. We have 10 fish, 2 shrimp and 2 anemones. We also have zoanthids, hard corals both are just frags, and some other things i can't remember the names of.

What type of filter do you have hanging on the back?
 
I would call 20% every other week kinda minimal for a new, heavily stocked tank. I do 10% every week, though after my last tank was up for a year I started to feel like I could back off a little. I hadn't had nitrate or algae issues for several months so I was comfortable stretching it out to 10% every other week or so.

It's tough with a 55 because you are generally restricted to hob equipment, which tends to be less effective as it sacrifices on ability in favor of space and noise. And when you're already cutting it close, each extra fish is another poop factory. FWIW I don't agree with feeding less as a nutrient control measure. The downsides of weak immunity and vigor and coloration make it not worth it to me. You don't want to overfed of course, but you need to provide sufficient nutrition first, and deal with export second, IMO.

When you are addressing accumulated nitrates, it can be effective to change a lot of water in a relatively short period. Like a reset. So, your nitrates are 40 ppm, and you do a 20% change, if you take 20% out of 40 you still have 32ppm. Not so great. But if you do another 20% change the next day you are close to 25ppm. Much better. Now, that's not accounting for the nitrates that are being added every day by your poop factories, but you get the idea.

It's very important to match temperature, salinity and alkalinity when you do more than 10% change; and it gets more important the larger the change. I can use cold water for a 10% change without a measurable effect on the temp of my tank. I did that one time for a large (I think 30% or so) change and killed 2 fish.

Once you knock them down they may still not be lowered much by water changes, but if you are lucky they will be bouncing around below 20ppm instead of 40. That's better for your inverts and eventually the bacteria that eat them will hopefully get more effective.
 
Nobody has seemed to ask you how much substrate and rock you have in your tank. Ideally you want bacteria to be processing the nutrients in the water, but this bacteria requires porous live rock and a sand bed to populate. 10 fish does seem like a lot for a tank that size and that age already, but if you do not have adequate aerobic and anaerobic areas for the bacteria to populate you will never achieve the nutrient levels ideal for the hard corals you are trying to grow.

Also, if you do not have a good protein skimmer you should not be carbon dosing as the bacteria populations can grow large enough to remove most of the O2 from the water column harming your livestock, plus if the skimmer is not pulling the bacteria from the water column then they will just release the nutrients right back in when they die.

All of that said, what is the state of the algae growth in your tank. As I have not seen you complaining about algae it makes wonder what test kit you are using and if you are getting accurate results. It could be worth taking a water sample to your LFS and have them test the water for you just to validate your own test results.
 
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