Chloramines & Nitrates Paradox

[Colin_T]

But if the water is coming in at a slow drip rate (1/2 gallon per hour is my target), won't the ammonia be seriously diluted, and neutralized by the biofilter pretty promptly?

Yes the ammonia will be used by the filter bacteria pretty quickly, but water flowing into a tank via drip system is not an efficient way to water change an aquarium. It just doesn't dilute the nutrients and disease organisms in the tank very effectively. And you need to break the chloramine into chlorine and ammonia before it goes into the tank otherwise chloramine will remain active in the tank for weeks afterwards.

 

[SmithPad]

Yes the ammonia will be used by the filter bacteria pretty quickly, but water flowing into a tank via drip system is not an efficient way to water change an aquarium. It just doesn't dilute the nutrients and disease organisms in the tank very effectively. And you need to break the chloramine into chlorine and ammonia before it goes into the tank otherwise chloramine will remain active in the tank for weeks afterwards.

Right, of course. My plan was to first run the tap water through a carbon block made for that purpose. I wouldn't dream of running the tap water directly to the tank.

I hear you on the efficiency thing, yet the internet is full of stories where people are claiming this is indeed working well for them. Even the discus forums ('m not doing discus). I feel my situation is a little different because my volume is so much smaller (29 gallon).

But I'm not married to the solution...just trying to understand it all.

 

[Colin_T]

I'm not sure if carbon removes chloramine. I know it removes chlorine, but the ammonia might prevent the chloramine being adsorbed by carbon.

Drip systems add a small amount of water at a time. The new water mixes with the old and some of the old water and some of the new water gets removed through the overflow/ outlet. Because some of the new water goes out with the old water, you waste a lot of water and the tank doesn't get flushed out that well.

If you put enough water through the tank then you do flush out nutrients, but you waste a lot more water than if you just drain the tank and refill it.

 

[SmithPad]

I'm not sure if carbon removes chloramine. I know it removes chlorine, but the ammonia might prevent the chloramine being adsorbed by carbon.

Right, I should have been more specific. I'm looking at Pentek's "ChlorPlus 10" cartridge, which is specifically formulated for chloramines.

Drip systems add a small amount of water at a time. The new water mixes with the old and some of the old water and some of the new water gets removed through the overflow/ outlet. Because some of the new water goes out with the old water, you waste a lot of water and the tank doesn't get flushed out that well.

If you put enough water through the tank then you do flush out nutrients, but you waste a lot more water than if you just drain the tank and refill it.

Yeah, I totally get that. I've run some dilution calculators to see the cost/benefit, so I still need to think about it. Knowing myself, I know I can't keep up 50% changes twice a week (which isn't keeping my nitrates below 20ppm anyway), so if a solution like this allows me to cut that down, even by half, I figure the fish will be all the better for it.

Thanks for the back and forth, it's really helping understand the bigger picture!

 

[seangee]

Or you could just throw a handful of water sprite or frogbit into the hood
In a few weeks it will turn into an armful and (assuming you do a weekly w/c) no more nitrate problem.