My BN pleco is broken. Need suggestions for another pleco

[hulkamaniac]

Originally Posted by JRagg

Yeah, nothing will eat that stuff. It’s a complete mess too. It is caused by nitrates bottoming out, which is easy to do in a planted aquarium with some fast growers (like you have). You need to start out by dosing nitrates to correct the root of the problem and you can try cleaning it off of your plants daily and seeing if it knocks the BGA back at all. If that is working you can continue to do that until it’s gone. Depending on how bad it is that may not work at all and a blackout may be required. If it is, clean as much off as you can and do a gravel vac with a large PWC. Black out the tank for 3-4 days, and clean up as much of the dying BGA as you can afterwards.

The big thing from that point on is making sure that you don’t let your nitrates bottom out again. Dosing will be required, especially with the plants that you’ve got in there.

Hope that helps.

Which plants do I have that are the really fast growers. I'm thinking I could add them to another planted tank I have where I don't inject CO2 and replace them w/slower growing plants. Also, what kind of plants should I look for that are slower growing.

[crazycat]

using an air stone increases surface agitation that will cause your co2 to outgas more rapidly. most people try to have as little surface agitation as possible. i however try to keep a little movement at the top to prevent stagnant patches. i also use an air stone at night when the plants are consuming o2. from my observation, my fish would usually huddle at the top of the tank, meaning that they were not getting enough o2, so i give them a bubble stone at night.

[JRagg]

I've never dealt with rotala, but every other plant you have is a fast grower. Anarchis, Swords, and Horwort all suck up Nitrates like there is no tomorrow. You want some fast growers in a tank with the light that you have. The CO2 is helping those fast growers outcompete the real algae. That is why you don't have real algae.

BGA is a completely different beast than normal algae. It is not algae. It is a bacteria. At those light levels you will have to dose nitrates so that it doesn't bottom out again. I am at "medium light" roughly 2wpg and I have to dose nitrates about once a week. If you get rid of it and keep nitrates from hitting zero (I shoot for over 10 on my AP test kit since it is so inaccurate at low levels) then it won't come back.

Some other plants to consider (that are slow growers) that may help compliment your tank after you get the BGA cleared up are Java fern and some anubias (I like nana better than normal anubias).

[hulkamaniac]

Ok. I'll check into the slower growing plants. I left the lights off yesterday and also didn't feed the fish. A lot of the algae on the rocks was gone and the dwarf gourami I had was picking at the stuff that's growing on the plants. Maybe I can cure the problem with more water changes and less feeding. I don't have a lot of money now to add more chemicals to the tank.

[7Enigma]

Originally Posted by hulkamaniac

The algae really started to bloom when I added CO2 to the tank. Maybe my problem is I don't have enough plants to compete for the CO2?

No that does not make any sense. My educated guess is that your nutrient levels are not being maintained and what you have is perfect conditions for algae. Adding CO2 just exacerbated the problem by giving the algae a carbon source (they already apparently have a nitrogen and light source).

You need to find out what your phosphate, nitrAte, GH, and be dosing potassium in the proper amounts.

[rich311k]

What kind of CO2 did you add(DIY or pressurized)? Inconsistent levels could easily cause algae as well. Most algae problems are CO2 related.

[7Enigma]

Originally Posted by coldmachineUK

I'm confused then: if increasing O2 does not displace CO2, then why would the suggestion of an airstone defeat the purpose of having CO2? Surely it would mean you could add both additional oxygen and additional CO2 to the tank...?
Particularly since during the night plants use O2. That way you could assist growth during both day and night...?
Do you turn off the CO2 at night? Plants do not use carbon dioxide in the dark. I also understood that CO2 injection causes pH to rise and drop between daytime and nighttime.

It's been said that CO2 produces beautiful planted aquaria. I've seen examples of that, but I've also seen examples where CO2 wasn't necessary. I suppose it's personal preference. If algae is becoming a problem though, then it would help to reduce CO2 levels perhaps. That was the gist of my suggestion.

As already said an airstone will increase the turbulence of the water which helps to gas out the CO2 that is dissolved in the water. While this sounds then like you should have a still surface, I'm waiting on a powerhead from Big Al's because I'm having the opposite problem. Too little flow near the surface causes nutrient imbalances which is causing my plants to have algae on them near the surface.

Many people that have pressurized CO2 do indeed turn the CO2 off at night since it is not needed. Those of us with DIY either add an airstone, increase turbulence (ie turning up the filter flow rate), or doing nothing.

CO2 is not needed in low light tanks. Under those circumstances light is what is limiting your growth. The 2-3ppm or so that is naturally found in the tank water from the air is acceptable enough to not cause problems. Once you increase the light level though, your plants start to demand more carbon. Not enough carbon, they slow/stop growing, but the rest of the tanks inhabitants (algae talking here) will flourish since their individual carbon requirements are much lower than a plant. In this case an airstone is actually a GOOD THING, since it will help to maintain that low level of CO2 at all times.

So the best thing you can do to keep a nice planted tank is to have pressurized CO2 that maintains ~30ppm along with an airstone that maintains a good supply of O2 as well. But not all of us have that luxury....

HTH

[hulkamaniac]

Originally Posted by rich311k

What kind of CO2 did you add(DIY or pressurized)? Inconsistent levels could easily cause algae as well. Most algae problems are CO2 related.

I added DIY. Two 2l bottle reactors connected to a t connector. Then the tubing is run directly into the intake of the canister filter.

[rich311k]

How steady are you levels? How often do you change bottles?

[JRagg]

Just curious hulk, did you decide what kind of algae it is based on the pics on plantgeek?

If it is Cyano (BGA) then the only reason CO2 would add to the equation is if it helped the other plants consume the nitrates faster.

If you are running a tank with 2-3 wpg like you say and CO2 injection, you will have to dose ferts to keep algae from taking over your tank.