C02 N00b Questions

[CEB]

I give up! You've convinced me to try this new-fangled CO2 thingy, and I want to go the DIY route because I can't really afford the £60 plus I need to get three canisters for my 250-275 litre tank. I want to get set up asap. I've read various threads, but I still have a few questions. Excuse me if they're answered somewhere else, but I'm overwhelmed myself with info.

1. The tank end of the tube is at normal atmospheric pressure, so even the slightest increase in pressure in the reactor is vented into the tank, so why is this considered to be a high pressure system?

2. I need more than one kit but until I get a CO2 level monitor, is one kit working full-power going to be too much for a 250L tank?

3. I suspect that using an airstone will be better than a ladder because the smaller bubbles have a bigger surface area (per minute) exposure, especially since smaller bubbles seem to take longer to burst on the surface than larger bubbles. Do you have any comments of experience please.

4. Isn't CO2 poisonous to fish?

Thanks so much. Any comments or suggestions will be appreciated.

 

[SuperColey1]

1. The tank end of the tube is at normal atmospheric pressure, so even the slightest increase in pressure in the reactor is vented into the tank, so why is this considered to be a high pressure system?

It's a case of the cannister can only hold so much so eventually it pushes down the airline until it comes out of the end. I wouldn't call DIY or Nutrafin high pressure

2. I need more than one kit but until I get a CO2 level monitor, is one kit working full-power going to be too much for a 250L tank?

1 kit will not overpower a 70l tank so you will be looking to use 3 or 4 x 2ltr bottles

3. I suspect that using an airstone will be better than a ladder because the smaller bubbles have a bigger surface area (per minute) exposure, especially since smaller bubbles seem to take longer to burst on the surface than larger bubbles. Do you have any comments of experience please.

an airstone produces larger bubbles and the CO2 will just go straight to the surface and be a waste of time you doing. The ladder stops the bubble going straight to the surface, as the bubble has to 'climb' the ladder and is therefore in contact with the water longer. You will notice a 4mm bubble becoming a 1mm bubble by the time it reaches the top of the ladder. hence diffusion

4. Isn't CO2 poisonous to fish?

CO2 is poisonous to humans but it is all around us. As long as you don't go overboard then the fish are OK and you won't go overboard with DIY believe me. Its when a full cylinder of pressurised discharges itself that you have a dead fish problem (from experience)


Andy

 

[nry]

Hmm, if you use a ceramic diffuser then there is certainly a decent pressure build-up, which is required to push the CO2 through the ceramic. If I disconnect a cannister to refill I get a fairly noticeable pressure release: the diffuser is at atmospheric pressure but the pressure required to push CO2 through ceramic is higher than atmospheric pressure hence the build up and maintenance of pressure.

I reckon you can overdose with DIY CO2 aswell, if you add too much yeast/sugar then you'll get more CO2 which can be too much.

I have 2 Nutrafin cannisters CO2'ing a 54litre tank feeding a ceramic diffuser. I add 1/3 teaspoon of yeast to each cannister, and even this can push CO2 into the yellow on my checker.

 

[CEB]

Thanks very much for your replies.

Nry, I'll start slowly, even though my tank is five times the volume of yours. I'll probably go for a ladder, rather than a diffuser (see below), so I hope pressure won't be a problem.

1 kit will not overpower a 70l tank so you will be looking to use 3 or 4 x 2ltr bottles

I will be using 3 eventually. I just need to drink more coke.

an airstone produces larger bubbles and the CO2 will just go straight to the surface and be a waste of time you doing. The ladder stops the bubble going straight to the surface, as the bubble has to 'climb' the ladder and is therefore in contact with the water longer. You will notice a 4mm bubble becoming a 1mm bubble by the time it reaches the top of the ladder. hence diffusion

I didn't realise that that much gas would be absorbed during the climb. Now I understand, thanks.

CO2 is poisonous to humans but it is all around us. As long as you don't go overboard then the fish are OK and you won't go overboard with DIY believe me. Its when a full cylinder of pressurised discharges itself that you have a dead fish problem (from experience)

I wonder if too little CO2 can be harmfull to fish. From what I've read, I might have too much surface aggitation leading to too little CO2. It's not just the plants that don't do well, new fish tend to die quickly too. The only thing that does really well is algae.

I had been advised that I had 'old tank syndrome' which I tried to rectify. Is there such a thing as a tank that's too clean? Currently I only have six fish and some new plant (that isn't doing well). I really want to re-stock, but don't want to waste a lot on money on plant that doesn't last. BTW, water conditions are very stable, so much so that I'm having trouble reducing the pH from 7.6 so I can introduce two plecs from my Mum's tank that was pH 6.0 but is now 6.8 (we're trying to meet in the middle).

SuperColey1, nice use of quotes, but it just takes too much time to match you

 

[SuperColey1]

SuperColey1, nice use of quotes, but it just takes too much time to match you

COPY/PASTE MY FRIEND

SuperColey1, nice use of quotes, but it just takes too much time to match you

COPY/PASTE MY FRIEND

SuperColey1, nice use of quotes, but it just takes too much time to match you

COPY/PASTE MY FRIEND

 

[CEB]

Ah, I see. Amazing what you can learn here.

 

[nry]

Can you not acclimatise the plec's as you do with new fish? Float them in a bag (or put them in a bucket) and add small amounts of tank water every 10-15 minutes, then remove some water, then do the same again. After 1-1.5 hours the fish should be OK with the pH change and adapt to any other water parameters.

 

[SuperColey1]

Plecs are normally quite hardy fish.

I put them in a large plastic mixing bowl in their water and float it on the top.

Then every 5 minutes put a quarter of the amount of their water from the tank into the bowl and after ½ hour tip and remove the bowl.

andy

 

[CEB]

Thanks for the tips guys. I'm usually super cautious when introducing new fish anyway. Perhaps more cautious than I should be. There was no rush to get the fish from my Mum's tank and into mine, so I thought I could give them the best chance by matching the pH of the tanks first. Can't wait much longer though, algea levels go from none to covering most of the glass in the space of two weeks. The plecs are going to have a feast.