« 1 (2) 3 »
nathangoudie nathangoudie
  • Home away from home
  • Home away from home
  • Joined: 14/2/2012 13:40
  • From Vietnam
  • Group: Registered Users Basic Membership
  • Posts: 1385
  • Posted on: 2/9/2013 17:24
Re: How effective is mangrove-filter #11
Suey,
Thanks for the information Suey, I had the problem about the substrate as you had once. However malaysian trumpet snails do really a good job on shifting the surface which prevents the gas build up. My shrimp tank is now really infested with MTS but with 4cm of sands, they're invisible until there's food. Best thing is they take care of any left over food and there's no need to worry about over feeding that much.

I'd really glad to try it again in bigger scale but the biggest I can go is 200l as my budget allows. But the idea that having a flow sounds necessary and maybe a power head will work.

Fishlady,
Correct me if I'm wrong but the main chemicals in water for keeping fish is Calcium and few other chemicals which make up kH and gH. So in theory if there's a chamber in the tank with water flow and lots of crushed corals, those essential chemicals might be replenish at some rate?
If that's true then water change could be minimized to maybe once per 2 or even 3 weeks?
Fishlady Fishlady
  • Tropical Moderator
  • Tropical Moderator
  • Joined: 6/7/2010 19:26
  • From Worcestershire
  • Group: Caresheets Moderators FK Supporter Registered Users Image Admin Advisers
  • Posts: 13707
  • Posted on: 2/9/2013 19:58
Re: How effective is mangrove-filter #12
Quote:

nathangoudie wrote:


Fishlady,
Correct me if I'm wrong but the main chemicals in water for keeping fish is Calcium and few other chemicals which make up kH and gH. So in theory if there's a chamber in the tank with water flow and lots of crushed corals, those essential chemicals might be replenish at some rate?
If that's true then water change could be minimized to maybe once per 2 or even 3 weeks?


That depends very much on the water supply and how much carbonate is in the fresh water for one thing. The other factor here in reference to my reply to LukeC is that his tank is stocked to a level suited to a modern biological filter and that is more stock than a plant filtered tank would normally be expected to handle.

Natural plant filtered tanks are stocked at a much lower level of fish so depletion is slower. Carbonates are important for maintaining the cycle but there are many other trace elements which also deplete and are essential to fish health which also need to be replenished.

Additionally, some evidence exists that a fish can be stunted by a build up of hormones in the water which also need to be removed by pwc, but again this applies to tanks stocked according to a ratio for a powered filter.
Onyxia Onyxia
  • Plants Adviser
  • Plants  Adviser
  • Joined: 31/10/2010 13:47
  • From London
  • Group: Advisers Deep End Registered Users
  • Posts: 600
  • Posted on: 2/9/2013 22:16
Re: How effective is mangrove-filter #13
I've got very hard water, dose fertilisers like theres no tomorrow and stock lightly so not a great comparison for Nathan but I'm not noticing any loss of GH and all water readings are very stable. I'm doing about one 20% waterchange every month or two and top ups at least once a week. My tank is supporting a lot of terrestrial growth so that probably helps:

Resized Image


I'm not sure its advisable but its definitely possible to keep a stable tank without a lot of water changes.
Fishlady Fishlady
  • Tropical Moderator
  • Tropical Moderator
  • Joined: 6/7/2010 19:26
  • From Worcestershire
  • Group: Caresheets Moderators FK Supporter Registered Users Image Admin Advisers
  • Posts: 13707
  • Posted on: 2/9/2013 23:55
Re: How effective is mangrove-filter #14
Top ups will be helping, plus all the additional elements in the ferts
finnipper finnipper
  • Home away from home
  • Home away from home
  • Joined: 21/7/2013 0:59
  • From Lancashire
  • Group: Takin' a break...
  • Posts: 319
  • Posted on: 3/9/2013 1:09
Re: How effective is mangrove-filter #15
"Correct me if I'm wrong but the main chemicals in water for keeping fish is Calcium and few other chemicals which make up kH and gH. So in theory if there's a chamber in the tank with water flow and lots of crushed corals, those essential chemicals might be replenish at some rate?
If that's true then water change could be minimized to maybe once per 2 or even 3 weeks?"


Calcium is important because fish take calcium for bone growth ect straight from the water rather than through diet. But there are loads of other biologically important minor and trace elements which very quickly become depleted without water changes unless they are supplied as additives.
As mentioned carbonates are important particularly in soft water areas where very regular water changes are required to keep them topped up.
Dissolved solids, nitrogenous waste, organic waste all need removing and although there is little research on the topic I am a firm believer that growth limiting pheromones also need keeping low. All these things rely on water changes for which there is no substitute.
nathangoudie nathangoudie
  • Home away from home
  • Home away from home
  • Joined: 14/2/2012 13:40
  • From Vietnam
  • Group: Registered Users Basic Membership
  • Posts: 1385
  • Posted on: 3/9/2013 6:38
Re: How effective is mangrove-filter #16
Just googled it and have some information about these hormones and pheromones.

In the wild, these are diluted or washed away by flow, rain, etc... But anyone know what actually consume them? I mean if they washed away then they will jsut simply move to new environment. Also diluting doesn't help that much in dry seasons as the water deplete.
Fishlady Fishlady
  • Tropical Moderator
  • Tropical Moderator
  • Joined: 6/7/2010 19:26
  • From Worcestershire
  • Group: Caresheets Moderators FK Supporter Registered Users Image Admin Advisers
  • Posts: 13707
  • Posted on: 3/9/2013 7:11
Re: How effective is mangrove-filter #17
I would expect that in addition to initial dilution, over time these are biologically degraded in nature. In a small closed system such as an aquarium this will not happen fast enough and so the build up is potentially harmful if no water changes are carried out.

Any depletion in water levels during dry seasons in the wild is pretty irrelevant as we're talking about immensely huge volumes of water and ratios of fish to water in comparison to a typical aquarium.
finnipper finnipper
  • Home away from home
  • Home away from home
  • Joined: 21/7/2013 0:59
  • From Lancashire
  • Group: Takin' a break...
  • Posts: 319
  • Posted on: 3/9/2013 9:21
Re: How effective is mangrove-filter #18
With regard to the growth inhibiting pheromones very little is known because although most experienced fish keepers accept their existence there has been no research in to it which is surprising really when there is so much aquaculture of food fish going on.

The way I imagine it works (and these are just my own thoughts with nothing to back them up) is that the pheromones have a limited life before breaking down naturally and that they have to reach a certain level in the environment before they are effective.
This would naturally limit how much biomass a closed body of water could hold and prevent the fish from out growing their environment.

It would also explain why the lack of water changes inhibits growth which it most definitely does. Think of guppy fry in a breeding trap in a community tank and how slowly they develop compared to similar fry in their own tank which has daily water changes even though the food is the same in both cases. I have done this with some sailfin mollies after taking some from a friend who bred them.
After 10 weeks the ones in their own tank were a little over 2" while the ones in the breeding trap still looked like 3 week old fry at 3/4"

In a busy community aquarium the pheromone levels are likely to reach a level where there is some impact on growth it is probably this which has probably given rise to the myth about a fish only growing to its tank size.

I stress though that there is little or no research about this and there could be an entirely different explanation about what we can observe.
suey2 suey2
  • Coldwater Moderator
  • Coldwater Moderator
  • Joined: 21/2/2006 14:46
  • From London
  • Group: Registered Users Caresheets Moderators Advisers Image Admin
  • Posts: 10089
  • Posted on: 3/9/2013 10:25
Re: How effective is mangrove-filter #19
i did find some stuff about growth inhibiting hormones/pheromones when I was researching for the INJAF article on growing to the size of the tank, I'll have to have a look for them as I didn't use them all so didn't reference them, might have them in my bookmarks somewhere though One of the most useful explanations I've had of what goldfish do (and not all fish do this) was from Dr Richmond Loh in reply to an email someone from PFK sent him when she was very kindly helping me gather info. He said that it's a competitive advantage mechanism rather than a growing to size of environment mechanism. While it can also cause the 'illusion' of growing to the size of the environment I personally think there are many and varied factors which all come together to cause this. The competitive advantage thing makes much more sense to me; suppress the competition, eat all the food, get the ladies and have less chance of being eaten by someone else!

http://thefishvet.com/2012/02/28/do-g ... o-the-size-of-their-tank/

Going slightly off topic, when my fish spawned last year and I had six babies they were all in the same tank (180 litre) for a few months until they were big enough to live with mum and dad and the difference in growth rates was phenomenal. One of them, a female, was consistently much much bigger than her siblings from the word go. One of the others is gradually catching up now, the other three singletails are roughly the same size as each other but smaller, and the only fantail is still the size of a three month old fry despite having exactly the same conditions as the others and just hasn't grown at all. I think she must have something quite fundamentally wrong with her growth system! But leaving her aside, the others in theory should all have been similar sizes but were quite radically different.
It's Not Just A Fish
finnipper finnipper
  • Home away from home
  • Home away from home
  • Joined: 21/7/2013 0:59
  • From Lancashire
  • Group: Takin' a break...
  • Posts: 319
  • Posted on: 3/9/2013 11:38
Re: How effective is mangrove-filter #20
That link makes sense, I have noticed that not all fish are affected in the same way. My Sorubim lima out grew a growing on tank unbelievably quickly despite the tank only being 60 litres and with two baby Senegal bichirs for company. The fish were to small to go in with the adults at the time so that was a nursery for them.
Within a matter of weeks it grew so much that it became a potential threat to the bichirs and had to be moved to the 'big' tank.

This is him/her grabbing some lance fish before the bichirs even realise its there, and it wasn't even 3" at this stage.

http://www.youtube.com/watch?v=W92WJcnKUAY

I notice the author refers to "hormones" I always thought that hormones acted internally i.e. in the blood stream and from an internal source, and pheromones acted from an external source i.e. in the environment.