Reducing Nitrate via Water Change

The amount of water changed in an established aquarium is basically the only way to reduce nitrate levels via water change. If you aren't getting results in reducing your nitrate to safe levels through water changes than you either aren't changing enough water and/or the water you're adding back into your tank is high in nitrate.

If you have a tank that has an unsafe nitrate level at say 80ppm (Parts Per Million) and your tap water has a safe nitrate level at say 20ppm than doing a 25% water change will not alter the nitrate level (it may reduce other things in the tank but nitrate won't be one of them). Even if you did numerous 25% water changes under these circumstances your nitrate would still go unchanged. Now if your tap water had a 0ppm nitrate level than any % of water changed would reduce these nitrate levels.

Given the above stats as before if you did a 50% water change than you would actually reduce the nitrate to 60ppm. If you continued doing these 50% water changes than over time the lowest your nitrate level could get would be 40ppm (which is a safe nitrate level). Keep in mind that the lowest your nitrate level can reach depends on the water you are adding back into the tank and in this case the only way to reach 20ppm would be to perform a 100% water change because that is the same nitrate level as the tap water. Another interesting thing to note is lets say you did a 75% water change and your nitrate is now at 40ppm and the following day you want to do a 50% water change to further decrease the nitrate. Doing that would not reduce the nitrate, it would actually raise the nitrate to 60ppm if the tap water is still at 20ppm. So it is possible to raise your nitrate level even if you are performing regular water changes.

It is important to know that nitrate levels generally increase overtime so, an aquarium can reach unhealthy nitrate levels (which generally start at 80ppm) which can cause "Nitrate Poisoning" in aquarium inhabitants. A gradual increase in nitrate may not appear to harm fish over time but it can harm/kill newly added fish that have not been exposed to this level of nitrate. One symptom of nitrate poisoning may be "Swim Bladder Disease" which affects equilibrium in fish. By measuring nitrate levels (I use Tetra EasyStrips to test my water) weekly it can help you figure out how much water you should be changing and possibly how often it needs to be changed.

Big water changes can have ill effects on aquarium inhabitants that have gone without regular water changes so, it is often best to start small and work your way to doing bigger water changes, as again you may not be changing nitrate levels at first but you are more than likely altering other water parameters (such as reducing any aquarium additives). By drastically reducing nitrate in an aquarium you risk putting the aquariums inhabitants through things like "Nitrate Shock" and some symptoms of this are listlessness, loss of equilibrium, and fish laying at the bottom of the tank.

Aside from water changes some other ways to help keep nitrate levels low is to not overfeed aquarium inhabitants and use nitrate removing filter media (which does not mean water changes should not be performed). There are also water treatments available which may help to reduce nitrate but some of these may also contribute more to polluting a tank causing nitrate levels to rise in the long run if water changes are not continued so, I don't particularly see a need in purchasing those unless the new water you're adding to an aquarium is very high in nitrate as well (such as water with a nitrate level over 40ppm).

Water Change via Pond Pump

If you have been using something like a gravel vacuum and bucket to do your water changes because you can't connect a water-flow control valve to your sink faucet (and at this point you've probably exhausted yourself), or perhaps your home doesn't have the best water pressure, or you don't want to waste as much water as with a typical water-flow control valve than what I am about to show you is a super simple solution and a total game changer!

Say goodbye to buckets and buy yourself a pond pump and enough hosing (that will fit onto your pond pump) to reach from your sink, bathtub, etc to your aquarium (and you may want something to hold your hose in place.. like a clamp or heavy object). 

How-To

Connect the hose and pond pump together. Set the pond pump into your aquarium while the other end of the hose goes in the sink drain. Plug in the pump and the water will remove the tanks water and go down the sinks drain.

To fill the tank back up you adjust your sinks water temperature as needed, close the sink drain (so it will continuously fill with water), and leave the water running (traditional sinks usually don't overflow as they have a top drain hole). Place the end of the hose into the aquarium and then plug in the pump by the sink and place the pump into the sink of continuously running water.

Once the tank is filled with clean water unplug the pond pump (assuming it doesn't have an off/on switch like mine), place your finger over the end of the tube in the tank and bring it to sink to drain out any excess water in the tube.

Additional Tips

Pond pumps don't really have a lot of suction when pumping water so you probably won't have to worry about fish, gravel, etc getting sucked up into these vents. If you are worried about small fry, etc getting into the pump than you can try placing the pump device into some panty-hose (or other fine fabric that water can easily travel through) and knotting off the fabric around the pump. 

Be sure your sink or tub is clean before filling it with water (vinegar is one of the best natural cleaning agents in my opinion) as sinks are one of the germiest places in the home (more so than the average toilet). You could also place a clean bowl inside your sink to place the pond pump in instead of having it set in the sink itself (which is probably the best way to go about this anyway), and this could also be beneficial if your sink doesn't have a top drain so that you don't have to worry about water overflowing and you could then leave the sink drain open instead.

I use the Tetra 140GPH Pond Pump, it comes with 3 different sized hose adapters (a 1/4, 3/8, and 1/2 inch ID) and has an adjustable flow rate (which gives off around 3 inches of head at its lowest setting and over a foot of head on its highest setting). Keep in mind the GPH when looking for a pond pump because that will control how fast you can get your water change/s done (with the 20ft vinyl hose I attach to this pump I can basically empty 1 gallon of water per minute). 

Altering Water Temperature

This week I had a semi-idiot moment (but still a lesson learned in the process) when trying to reduce the current water temperature in my aquarium momentarily (per another experiment of mine). Basically I have been told that when doing a water change you should keep the temperature of the new water within 3-5F of the aquariums current water temperature (as to prevent things like 'Ich' from happening). However, if you have a 79F tank, change 25% of the water (in say a 20 gallon aquarium), and add in 74F (which is 5F lower than the current water temp) water to replace that 25%... guess what, the aquarium water only dropped 1.25F degree in combination with the current tank water temperature (which just wasn't going to do because I wanted the overall water to become 74F momentarily and not 77.75F).

As a side note the upside to adding in cooler water than the tanks current temperature is an increase in the waters oxygen level (which is why I feel when you do a water change to always add in cooler water than the tanks current temp). Did you know water at 77F/25C has an oxygen solubility level of 8.6mg/L? Which means that the average oxygen level in a typical indoor freshwater aquarium is probably going to be around 8-9mg/L. Water at 32F/0C which is 'freezing point' has an O2 level of 14.6mg/L, while water at 212F/100C which is 'boiling point' has an O2 level of 0.

To break it down if I did a 50% (1/2 the tanks water) water change I would need to add in 69F water to my 79F for it to average 74F, which is a 10F temperature difference from the tanks current temp. So if I am only changing 25% (1/4 the tanks water) of the water I would need the new water to be 15F below 79F which would be 64F.

Now you may be saying that colder water is denser than warmer water (thus meaning the cold water would sink to the bottom of the tank) and that 'would' be problematic for aquarium inhabitants. However, when you add cool water to warm water the two temperatures combine together (because heat rises and cold sinks), but if you added hot water to cool water (thus reversing the order) then the two would take time to merge together (the later case could be problematic for aquarium inhabitants). Don't believe me? Than checkout this video on water density. So, if you happen to be using a tube to fill cooler water back into your aquarium you'll want this tube to be closer to the waters surface and not at the base of the tank in order to allow the two water temperatures to better merge together (unless of course you have other intentions for doing so).

Treating Ich on Ranchu

This past week I made a big mistake thinking that my ranchu would be fine in a temporary bucket of water while I cleaned out the aquarium. Well, it took me awhile to get around to actually cleaning my tank so I transferred my ranchu into a new bucket of water and they ended up going through a drastic temperature change (ranchu can only handle around a 3-5F temperature change at time) and thus suffered from it. Bumblez is not at all a fan of cold water and thus he began slowing down his swimming, while Oakki had broke-out in ich on the front of his wen. Luckily I was able to remedy both of them at the same time, here's how I cured and treated the ich in under 3 days (be sure to treat ich ASAP)...

1: Do at least a 50% water change to the aquarium water (be sure the new water added in is within 3-5F of the current tank water temperature), and treat the water with Seachem Prime according to directions (Seachem Prime helps reduce stress, helps slime coating, and dechlorinates water).

2: Keep the water temp in the aquarium around 74-76F (I use an Aqueon heater), as this seems to be an ideal temperature for ranchu in general.

3: Add 1-TBSP of Aquarium Salt (I used the Jungle brand) per 8-10 gallons of water (aquarium salt reduces stress, provides electrolytes, and cleans.. it may also raise your pH so be sure to dose accordingly). Although it may not be necessary, I added in a pinch of aquarium salt everyday after this initial dose until my ranchu no longer showed signs of ich.

4: Turn off any aquarium lighting to reduce any stress caused by glare, etc as these fish have already undergone enough stress at this point.

5: Be sure to run an air diffuser in your aquarium (along with a 24/hr running filtration system) for at least several hours a day to insure the fish are getting plenty of oxygen in the water (this is very important if you are using any other water treatments to remedy your fish outside of what I have on this post), this is especially important for smaller aquariums and/or ones with a higher temperature.

I hope my ranchu ich remedy works for others just as well as it did for my ranchu, and be sure to do another 50% water change a few days after having done the first one as to reduce the risk of having ich spread, etc (just be sure the new water you're adding into your aquarium is in the ideal temperature range as I mentioned before, too drastic a change may only worsen or cause the ich to reoccur). Good/adequate water quality can solve a lot of problems (be sure ammonia levels are also in a safe range, preferably no traces of ammonia, this is especially important if you have a small or overcrowded aquarium).