Discus Immune Systems/Natural Selection

[Discmaniac]

Hello All,

I have some questions that I know many of you can answer. I was wondering why it is necessary to do say 30-50% WC's every day? I am willing to do it and am doing it now that Carol turned me onto the garbage can with heater and airstone (sure makes life easier, thanks).

Do Discus have weak immune systems? I was thinking that in the dry season in South America the water quality has got to degrade for these fish which would expose them to lots of pathogens, but they seem to survive. And yes, wild caught specimens still require the same care (if not more) than our domestic stock. Maybe wild-caught fish have a higher parasite load to begin with?

Are the frequent WC's we do keeping most, if not all the weaker fish alive to pass on their genes to future generations?

What if an individual stopped doing daily WC's and started to do them weekly? I don't want to be the first person to try this since I only have four fish!, but was wondering if anyone has and what came of it. I'm assuming it must have been disastrous.

You all got me thinking that I should put My Angelfish and others into the 29g tank that houses the Discus (too small) and put the four juv. Discus into the 55g that currently houses the Angelfish. I now know where my priorities lie! The only problem is that the 55g is a fully planted tank. What should I do? I can already hear the responses---buy another tank!!!!

Thanks for reading this, and responding if you chose.

Bill
The novice :D

[Carol_Roberts]

Sorry, I can't explain it.

I don't know why water changes work, but they do.

LOL, I can't explain why electricity works either . . . .

[Discmaniac]

Thanks! :) :) :)

[Ralph]

For a fish species to become a part of the commercial aquarium trade, they go through a thorough screening to make sure they can handle a wide range of environmental situations. In other words, for Pet Smart to sell a fish, that fish has to be able to handle neglect and well intentioned, but inexperienced owners.

Many species of fish don't make the cut because they aren't adaptable to such a wide range of environmental factors. But because of their natural beauty, discus made it into the trade, in spite of the required higher temps, their preference for lower pH and softer water, and especially in spite of their need for clean water. Discus keepers are willing to do the extras to keep their fish alive and healthy.

It's not specifically their immune system, it is just that there was no evolutionary reason for discus to be able to live in water with high waste concentrations. So they aren't really weaker than other fish, they just aren't quite so adaptable as other aquarium fish.

I'd keep the discus in the 29 for the time being, the water changes are much easier. The trick though, is making the WCs as easy for yourself as you can.

A weekly 70%WC compared to 10% daily WCs is almost the same. You have the same average amount of waste in the tank, but there are greater fluctuations in waste levels with the weekly changes.

[chirohorn]

A weekly 70%WC compared to 10% daily WCs is almost the same. You have the same average amount of waste in the tank, but there are greater fluctuations in waste levels with the weekly changes.


I've read this before in another post, but I don't think it's entirely accurate. This assumes that when doing a W/C, the only thing being siphoned & replaced is water. However, we know by experience that we're wanting to siphon off the 'dirty' bottom water i.e. the fish poop or uneaten food.

If this is removed daily, there is a decreased chance for ammonium, nitrates, nitrites to come about vs. a weekly change. The overall amount of water exchanged is the same, but the tank changed daily should have a lower level of harmful chemicals (assuming the beneficial bacteria load is the same). That's my $0.02.

[Discmaniac]

Lots of good discussion.

What I'm getting out of all this is that the WC's remove potential pollutants that a non- functioning filter will not remove, i.e. Nitrite, Ammonia, Ammonium. On the other hand, if a biological filter is functioning at optimum capacity the only thing it won't do anything with is Nitrate [N], right? Thus the need to carry out WC's which also lessen the bio-load on the bio-filter.

As far as adaptability goes, I can think of one other soft-water Amazon basin species ---Altum Angelfish. I hear they need just as much TLC as Discus. Has anyone had much experience with these fish? Are there other Amazon Basin fish that require this much care?

One could make the arguement that if the Discus were exposed to the same parameters in water quality that a typical tropical fish would be exposed to that in the end the strongest, most adaptable fish would survive to pass on their genes to future generations and would then be capable of being mainstream pet trade fish. That is, if some were able to survive and someone wanted to carry out this experiment in evolution.

As far as ease of WC's go, the 10 g/day regime is working fine for the 29g. I am going to get another 55g though. The local Wally World had them for $199.99 which included tank, hood, and stand just after X'mas, but I snoozed and they sold out.

Does anyone know of any good supplier websites that are reasonable?

Thanks,

Bill

[Ralph]

Chirohorn, I agree with you. And I was trying to say that (it was three hours past my bedtime). There was an unstated assumption that solid wastes were being removed. And although the total buildup of liquid waste is the same for weekly and equivalent daily WCs, there is often higher waste amounts in the tank with the weekly changes (I do daily).

[Discmaniac]

Hi Ralph,

If the bio-filter is functioning properly all the waste should be converted to Nitrate [N] right?

From the looks of things a Discus has trouble dealing with high concentrations of [N], IMO.

It's too bad no one has researched this, or maybe someone has? Years of experience?

Bill
The Novice

[Aquarius]

I think ANY fish will grow much more if the W/C's are of a large amount. I have had many other Tropical fish that have grown very large, do to this fact. IMO, fish will grow to the size of it's envoriment, thus by the large W/C the Discus thinks it's in a larger volume of water..

Just my 2 cents worth :)

PS. I could have my Wet/Dry running with no W/C for 3 months and have 0 Nitrate, still I don't think the discus would grow as nicelt :)

-steve

[Discmaniac]

Steve,

What you said makes a whole lot of sense. One question though. If I do 33% WC's every day on my 29 g tank will the Discus get as large as they could in a 55 g tank? My gut feeling says no, but maybe with the fresh water turnover in the 29g tank..........?

What I would like to see is that they get as large as they can get without having to pay off the national debt I could get into if I got everything for these critters that I want!

Bill 8)

[Ralph]

Nitrate is bad for discus in high concentrations but it is not the reason we do WCs. Planted tanks typically have 0% nitrates, in fact plant people actually add nitrates for the plants (but keeping it at 10ppm or less). But even in planted tanks, WCs are still required for healthy fish.

If it is not just nitrates, then what is it? That's the hard part. To prove something, you have to be able to limit that one substance in the water while keeping others constant. And there are so many different things coming off of or out of your fish. The possible culprit is not even limited to those, it could be the biproducts of the substances, or bacteria that live off those substances, or substances expeled by bacteria in or around the discus. And what if it is a combination of two or more of them? You get the point.

Steve, I have rummies in a discus tank and rummies in a tetra tank, which doesn't get even close to the same WCs, the rummies with the discus grew much faster and bigger too.

[Aquarius]

Yep, thats why my Bleeding Hearts are huge! I read a story about how Jack W. did a thing with a 2 gallon and a 20 gallon tank with fry. Massive W/C on the 2 gallon and less on the other. The ones in the 2 gallon grow faster and bigger..

Can't recall the whole story without looking it up, but also read it somewhere on one of the boards.

Steve, Could you explain to me how your wet dry filter is removing nitrates?

Mike

[Aquarius]

Mike, I had read many a storys on the fact that Wet/Dry filters would build up the nitrates. Well, I really never went that long without some water changes, but nothing more then 15-20% a week. Thus to me, I never seen a build up in them.

Yet, I'm no expect on Wet/Dry's, this being my first true one, so maybe it takes much longer time frame, as I know that was the problem with Wet/Drys in saltwater, correct?

-steve

[Discmaniac]

So will the fish in my 29 g tank grow big and fast if I keep up the 33% daily WC's?

I'm still going to get another 55 or larger when I get the $$.

Thanks,

Bill

[Carol_Roberts]

Everything else being equal . . . . Discus in a 29 gallon tank with 33% daily water changes will grow bigger than those who get smaller or less frequent water changes.

[Discmaniac]

Will they grow faster in a 55 g tank with the same WC regime (33% daily)?

The only problem with this is that my RO unit only makes 18 g/day. A new RO unit in the future is on the list of must haves.

Does anyone use softened water? I would think the sodium [Na] would have a negative effect, but am willing to use it if it gives me more leeway with regards to tank #'s and size and of course, if it isn't harmful to the critters.

I would assume that if it is aged the pH would stabilize. It's about 8 straight out of the tap. Talk about soft though !!!!

Any thoughts?

Thanks,

Bill

[Carol_Roberts]

You should do a 33% daily WC in a 55 for grow outs. I've read on the board that some people with whole house water softeners tap into the water supply BEFORE the softener as the salt is not good for discus. Others with lots of iron, etc. run the softened water thru an RO.

Did you post the GH and pH of your water before it goes thru the softener - perhaps you could test an outside spigot for watering lawns?

[Discmaniac]

Hi Carol,

The water at my home before it gets softened is as follows:

GH 35 deg or 626.5 ppm

KH 6 deg or 107.4 ppm

pH 8.4

Do you think they'd live very long in this stuff? The water looks (is) yellow!!!! and smells very strongly of chlorine.

Could I even use any of it to mix with the RO water. I wouldn't doubt that a cup/gallon of this water would be enough to shoot the TDS's through the roof!!

Any ideas?

Thanks,

Bill

[Carol_Roberts]

:o You're out of my league.

[Discmaniac]

What do you mean?

[Carol_Roberts]

LOL, your water is very, very, very hard. Three times as hard as mine. The more experienced water guys need to advise you.

I'm betting your RO is going to see a lot of use. You'll use the RO on the water thas has been through the water softener and depending on the make-up of your water you my not be able use your tap to add back minerals at all.

[Don_Lee]

Bill,
I am far from a water expert, but from the information you have provided so far I would say just use RO water and some remineralization agent like RO Right. That water sounds too nasty to use at all IMO. IF you wanted to try to use it, I would test if for ammonia/nitrates/nitrites, and begin to add some to your storage/RO water to try to get the right mix. It will take experimentation. Again, I would not bother, I would just get the RO Right and use the RO water. You could consult with the resident RO expert, Randall, and see if you could upgrade your RO system too.

HTH,

Don ;D

[Discmaniac]

Thanks for the replies Carol and Don,

Yes, this water is ugly to say the least. I am using 1/2 tsp. of RO Right/10 g of straight RO water. I have a one year lease on the RO system, but I think I'll upgrade so I can get a higher volume of water/day. I should have bought one outright. (Live and Learn).

The water treatment guy said that if there wasn't a softener that the membrane would plug up fast.

From what I've heard, here in farm country the municipalities have to mix water from different wells in order to keep the nitrates under the EPA limits which, I believe is 10ppm. So even if I could use the tap water there would be the concern that I'm putting nitrate laced water in my tanks! What a sad state of affairs as far as the environment is concerned.

I will for sure be taking your advice and just use the RO water. The fish are very happy and I don't want that to change.

Thanks,

Bill

[Don_Lee]

Sounds good Bill, I would have a GH, KH, and pH test kit available so you know your water parameters with your RO too(if you do not already.)

Don ;D

[Discmaniac]

Hi Don,

Yes, I will keep the test kit handy. The parameters of my RO water are:

GH 0-1
KH 0-1
pH 6.8 after it stabilizes in the trash can for a while.

Thanks for all the help,

Bill :D