Major algae/co2/ph crash! HELP

Booswalia

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Apr 16, 2003
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Prince Edward Island
www.sonnys.ca
I knew it was going too good. My tank was doing very well until a few weeks ago when my co2 tank said it was time to refill. I didn't have the washer in place and it emptied in just a few weeks. So I put a DIY bottle on and got the tank refilled. I put the pressurized tank back on last Friday and since then I've had trouble getting it regulated. I can't seem to get my pH to drop to where it normally is. I put a bubble counter on and if I set it at about 3 bubbles per second I don't see any bubble coming out of the filter, where I have it connected. If I turn it up any higher I get tons of bubbles. So my pH has been swinging while I try to get it set just so.

Anyway.... I've been having a major break out of what looks like staghorn algae since the co2 thing has been happening. I removed a bunch of leaves and within 36 hours I've got more algae growing than what I took out. It's everywhere.

The Co2 seemed to have kicked in while I was at work today and this evening my ph read 6.2, (normally it's 6.8 or 7.0) So I did a 50% water change and got it back to about 6.6. (My fish are not happy about this.)

I'm really trying not to panic. :\ But I'm not sure what I should do. Any ideas or suggestions? I haven't added any ferts since the water change and I have the tank covered. No light or Co2 until I figure this out.

Tank specs
25 gallon
110 watt cf lighting on for 11 hours/day
Substrate 100% Seachem's Flourite
Hagen Fluval 2 Plus underwater filter
74 degrees
Mostly fast growing plants right now
pH normally 6.8 to 7.0
kH 5
Nitrate normally around .3 to .5
Phosphate .3 to .6

I've been doing the following fert routine.....
50% Weekly water change
1/4 tsp K2S04 (Nu-Salt) 1xweekly
3ml Flourish 1xweekly
5ml Flourish Iron 2xweekly
1/4 tsp NO3 (Stump remover) 2xweekly
2 drops KH2P04 (Fleet enima) 2xweekly
 
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What do you have your outgoing pressure set at? It's much easier to regulate the flow with your needle valve if you have the outgoing set at, say 8psi than at 20psi.
It sounds like you've had this problem only since the CO2 went out on you, correct? If so, what you need to do is re-set to where you were before. Aim for 6.8 now and once things settle in try for 6.7 as a target pH.
I suggest you turn the CO2 back on, clean up as much algae as possible, do another 50%er and start up the ferts again.
The fish are going to be ok as long as the water is "clean". The water change will do that for you.
Lose the iron for a while. IMO your plants don't need that much iron. Dose 5mls. Flourish after the water change and if things look ok another 5 at mid-week.
Are you testing for your P and N levels? Seems like you are under-dosing them, but can't tell without testing.
Len
 
The CO2 is being fed into my filter which has a place on it for adding an air line. It really just pushes the CO2 into the water. Right now my pressure is set at about 12psi.

Yes Len, the problem did start with the CO2 going out.

I do test for P and N levels, and you are right, they are a little low. I don't know why but I always hesitate to put more than 1/4 tsp of NO3 or 2 drops of KH2P04 at a time. It seems like a lot. Perhaps I not only need to adjust the amounts, but I also need to adjust my thinking. :\

Thanks for the advice. I will try it out.
 
First, make sure your CO2 system has absolutely no leaks. If that means somehow dipping all the connections in a container of water that's what you have to do. I don't remember what size tube you have but I can't see any reason a 5lb. tube shouldn't last you for 3-6 months, minimum. Keep an eye on the tank pressure and when it says 600psi, run it over and refill it.
I would re-set the out going pressure at 8lbs. max. This will make it easier to adjust your needle valve to a finer feed.
P should be 1.0 at all times. N should be 10ppm at all times or as close to these values as you can make them. The beauty of the weekly 50%er is if you err slightly it will re-set the tank.
Iron can cause algae issues and worse if you're not careful with it.
Plants store Iron.....yours are probably loaded.
Every tank is different and responds differently. Keep testing and you will learn what yours uses.
Len
 
hey boos, are you using the blue or green silicone tubing for your CO2, and what type of check valve?

My opinion, the cheapy check valves are corroded by the CO2 and once the pressure is off the inlet and the flap closes, it will stick shut except for high pressure. I have recently switched all of mine to brass or stainless check valves for this reason. Each time I woudl change the CO2 bottle(s) I would have a hard time getting the flow working correctly again (except when the pressure was too high for my liking). Also, I have noticed that the clear airline tubing always seems to gunk up at the inlet to the filter, but only when the bottle is off and the pressure is off the line. Since I changed over to the silicone tubing, many of the "mysterious" flow issues have gone away.
 
I'm using the greenish blue silicone tubing. I would call the colour aqua. And yes I am using a cheapy check valvle, but that's because I can't get a better one here.

I took the bubble counter off and put the tubing that came with my Hagen CO2 on and now it seems to be working fine.

Here is what I've done so far.....
Removed most/some of the algae
did a 50% water change
Took the bubble counter off
added 1/4 tsp NO3 (stump remover)
added 3/4 tsp K2SO4 (Nu-salt)
added 4ml iron
These are my readings right after.....
pH 7.0
kH 5
Nitrates 1
Phosphates .05

How long should a person wait before doing test after adding ferts? My nitrates still seem very low even after adding a 1/4 tsp. Is that because I didn't wait long enough?
 
You should get a good reading in about 2 hrs. after dosing N and PO4. See what you get in the morning and add more if needed.
What kind of test kits are you using for N and P? Are they in date or possibly expired? Seems like with a 25 gal. you should be registering more than 1ppm N, but I don't know how long you waited before testing either. You don't mention how much P you dosed. Test that again in the morning. Don't be afraid to shoot for 10ppm N and 1.0ppm P.
Once again, IMO you should not add any more Iron for at-least a week or two. This could be contributing to the problem, not a solution.
If you are dosing NuSalt you are dosing KCl(potassium chloride) which is ok. Just thought I'd mention it. K2SO4 is potassium sulfate. Either one is ok to use.
When you test in the morning also check your pH so you'll know what your CO2 concentration is.
You may have to work on the algae for a while but with the restoration of the CO2 and good fertilizing, you should see some improvement soon.
Len
 
I used a Seachems test kit about 15 minutes after adding the ferts. They don't have expiry dates on them, but they do include a reference sample which checks out fine.

This morning my Nitrates are reading 0 and my pH is 6.8

I suppose the plants used up the little that was there over night. I will add another 1/4 tsp before I go to work and measure again this evening.

As for P, I didn't add any. I just measured what was there. (I'm thinking.....limit that one to control the algae) I will hold back on the iron for a while though.

And Len, as for those KCIs, K2PO4s and FeSO3s......I will never get them straight. That's why I always put the product name next to them. I struggle terrible with acronyms, and at least they have a connection that could possibly fire a synapse or two. I can't find any way of connecting a K to potassium or an Fe to iron. And since I've never taken chemistry I can't put that alphabet soup together. So you're just gonna have to live with my long versions. :P

Thanks for all your help, by the way.
 
From Boos:
"I suppose the plants used up the little that was there over night. I will add another 1/4 tsp before I go to work and measure again this evening."

Sounds like a good plan.....check in the morning and if needed, add 1/4 and do the same again after work.

From Boos:
"As for P, I didn't add any. I just measured what was there. (I'm thinking.....limit that one to control the algae)".

I know how you feel.....most of what we are taught about phosphates is that they are not good and to limit them. But in a relatively high tech tank it's a different ballgame. With good light and CO2 they need ALL the elements....PO4 being a major one. When I started dosing PO4 I went with 3 drops. When it wasn't enough to keep at 1.0ppm I went to 4 drops. Still not enough....anyway I now dose 6 drops, 2 or 3x a week and have found the level I was looking for.

From Boos:
I will hold back on the iron for a while though.

THANK YOU VEEEEEEEERY MUCH !!!!!!!!!!!!!!!!

Len
 
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