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gecko
Tue Jul 11, 2006, 02:14 AM
Hi there,

I have only ever owned hardy lil' tropical fish, however, sometime over the next few years, I would love to upgrade to discus.
I have a 240L tank and I hope to have a planted community tank, with some little (but not bite-sized!) tetra friends.

Funnily enough, time is not a constraining issue, but I have problems justifying the large, regular water changes to my family (We live on rain-water tanks but don't recieve much rain, and as such we must be rather water-conservative).

So, my question is: Can I feasably decrease the volume and regularity of water changes, while still keeping happy fish (Or should I restrain myself to admiring other people's discus)? What could I realistically get the volume/freq down to, and how?
ie. Have a heavily planted, understocked tank?
Invest in an effective filter (or set up some elaborate and probably time- and-money-consuming system that takes over the loungeroom)?

mcloughlin2
Tue Jul 11, 2006, 02:34 AM
Some way to minimize the need for water changes

1) Run the best cannister you can afford on the tank (or better yet two!)
2) Invest in a small powerhead filter inside the tank to prevent "dead" spots occurring (Piles of waste that build up due to lack of current)
3) Stock the tank with as little amount of fish as possible...so i wouldnt put anymore then 4 discus in your tank along with some tetras...
4) Use the best filter media you can afford to buy (Will provide a large amount of bacteria to help deal with waste)

There probably the major points that need to be considered...

If you do that you would only need to do a water change once every week or two..

HTH

mcloughlin2
Tue Jul 11, 2006, 03:28 AM
I would also not go any lower then 20-30% water changes every 2 weeks... :wink:

taksan
Tue Jul 11, 2006, 03:44 AM
Hi there,



So, my question is: Can I feasably decrease the volume and regularity of water changes, while still keeping happy fish



The short answer is ..... no
If you want to keep healthy fish you must do water changes in line with your stocking level.
Filters do nothing to help with nitrates which is why you do water changes.
If you want to invest in a Nitrate reductor then its certainly possible to minimise water changes to 30% a month with light stocking density.
But they are expensive .....
A very large Heavily planted lightly stocked tank with a Nitrate reductor is really the only way to do this .....

*Chris*
Tue Jul 11, 2006, 04:05 AM
like taksan stated probably give it a miss last thing you want is your family going without water for the sake of your fish
:P

samir
Tue Jul 11, 2006, 04:54 AM
a denitrator would be the only way to go, you can make a diy one for about 20 bucks, but you really need to read the instructions a few times and get the waterflow right otherwise you can get h2s (rotten egg smelling gas), maybe you could make one and try it out on some real cheap fish first. once it starts working ok (which can take a couple of months) it will enable you to do the 30% changes that Tanksan mentioned.

gecko
Wed Jul 12, 2006, 12:40 AM
Thank-you so much for all of your help!
Now, could I just work through a few of your points and make sure I understand ? (please bear with me here!)

Mclouglin2, with the stocking rate, would the no more than 4 discus be juveniles, which i would then have to move to a bigger tank, or could they stay in the 240L as adults, and still be understocked?
Also, when you mentioned the "best filter media you can afford", is the quality of media dependant on the surface area to volume ratio for a large population of bacteria (in addition to mechanical filtration)?
(Just checking as the local aquarium suppliers seem to try and sell me the most expensive thing, without really understanding how it works or if it is even applicable to the situation!)
By the way, your avatar is just stunning!!

Taksan,
Would it be possible to elaborate on how the Nitrate reductor works? I have done a quick search, and I’m confuzzled! Do they use the enzyme Nitrate reductase? At a stab-in-the-dark, I would guess that this is what happens, but one site seemed to imply that they actually have a binding agent that reacts with the nitrate - and this worries me as, while it works it may be great, but as soon as you reach your limiting capacity/use up all of your agent, I assume there would be a large nitrate spike. Please do correct me if I am completely lost here!

A.I*Fishboy,
He he – had to laugh. They are a supportive family, but I can’t imagine them being to impressed with “No showers tonight – the discus need a WC”.
Don’t worry, I think I shall try and perfect the filtration system, and invest/make a nitrate reducer /denitrator and see how effective it is. If I can’t get the water changes down enough (without compromising water quality of course) then it looks like no discus for me – my tetras can enjoy the denitrator instead!

Samir,
The DIY denitrator sounds interesting. Are there any sites you would recommend with DIY instructions (or have any tips to add)? I admit here that I haven’t yet had much of a look around the internet, but would you be able to go over the basic principles for me?

Sorry this is such a long post!
Once again, all of your help and knowledge is so very much appreciated,
Gecko

FishLover
Wed Jul 12, 2006, 02:16 PM
there are some Nitrate removal media you can put in your filter. It need to re-chagred every few weeks.

I had to go on vacation for 5 weeks and there was no way for me to change water. I put the media in and came back after 5 weeks and everythign was fine.

Do try to feed less if you are doing less WC. You may want to get something that can test your Nitrate level in the tank. That way you know when to re-charge your Nitrate removal media or do a WC.

I would still do a WC at least every month or so.

revkev
Wed Jul 12, 2006, 10:41 PM
see this link for DIY Coil Denitrator Plans and how they work.
http://saltaquarium.about.com/od/proteinfiltersetups/l/bldiycoildenitr.htm

stonedavid
Sat Jul 15, 2006, 10:52 AM
Have you got bore water and if so what are the stats on it. Some people dont consider bore water as some areas they only use it for stock and watering produce. Just a thought.
Rgds
Pete

lesley
Tue Jul 18, 2006, 09:49 AM
I use rainwater and during no rain times regularly visit friends and beg for a shower or come with baskets of washing needing to be done!

I have been through periods of extending water changes up to two weeks when our last tank got down to 18" of water (including the mud at the bottom of the tank). I don't think the fish were overly impressed! I did this with a very heavily planted tank - using the plants to filter and clean the water. In my experience a cannister filter will not make any difference to water changes. You will need to make sure you vacuum the substrate very thoroughly when you do do a water change. I don't think this is a substainable routine for long periods.

We have gone the way of increasing our water catchment, buying a very economical in water washing machine, having short showers without the pressure pump running, using our grey water to water the garden (and don't waste the water from your water changes) and generally using less water ourselves and using what we have for the fish.

If you are going to try, I think you need a large tank, minimum 6'. lots of plants and keep a close eye on your fish. I really don't think that water changes of one week and over go well in the long run, but I do think that it would depend on stocking rates and plants.

It is my belief from reading on this subject that nitrates are not the be all and end all of water quality. Although during the periods I mentioned above my nitrates (usually run at about 5 ppm) didn't go over 10, I still felt that the fish could have looked a little better.

These are just my experiences, and others may well have found different!

nicholas76
Tue Jul 25, 2006, 06:11 AM
Im starting to sound like a promo guy for this product but!!

throw in a packet of Bio zorb and Nitra zorb in your cannister that will help.

Cynical
Tue Jul 25, 2006, 06:37 AM
what about a planted sump? something along the lines of 40-80L with good lighting and fast growing weed like plants. e.g. wisteria.
could use up your nitrates pretty quickly.

just a thought...

Cynical

samir
Tue Jul 25, 2006, 07:03 AM
i read somewhere that the amount of plants you need must be at least 30% of the area of your tank. so for a 6X2X2 you'll need at least a 2 foot cube crammed with plants for it to work.

Cynical
Tue Jul 25, 2006, 07:28 AM
i'm not sure on exact calculations, but surely it would reduce the amount of nitrates. i wouldn't recomend someone to stop w/c, but i would say you could reduce it. maybe less water per w/c with a good gravel vac.
if i had more room i'd do a planted sump. bonus of being able to hide some of your equipment in there, and have more total water volume, while still having a tank that looks full of fish.