Too Many Fish?

Hi,
I'm afraid this is not an accurate assessment. Nitrate can't cause algae. Neither can Phosphate, Iron nor Molybdenum. Your algae was due to higher NH4 in the presence of the lights, which perhaps the lower biomass was less able to deal with.

Cheers,

 

shane,
NH4 is constantly being produced in a tank and this production never ceases. It is independent of aquasoil, although this could exacerbate the problem. Uneaten food, fish urine and feces as well as detritus from the bits and pieces of the plants all decay and produce ammonia, every minute of every day. In a running aquarium NH4 never "=0"...ever.

The job of the filter bacteria that live on the bio-media, the bacteria that live in the water, in the sediment and on the surface of the plants and on any other submerged surface is to consume NH4. When more NH4 is produce than can be consumed by the bacteria then algae have a chance to consume the remaining NH4 and proliferate.

Healthy plants do consume some NH4 as well but if your dosing is suspect or if your CO2 is sub-par then the plants become unhealthy and lose their ability to remove NH4, thus they actually contribute to the problem by leeching NH4 and nutrients into the water.

This is a fundamental principle of algal proliferation and is one that you need to understand if you want to minimize the problem. The levels of NH4 that can result in algal blooms cannot be measured by your ammonia test kit as these kits have only enough sensitivity to determine the level of ammonia that is toxic to fauna.

Algal blooms can be triggered with NH4 levels far below what can be measured by hobby grade test kits. The higher the light, the greater the susceptibility to triggering the blooms.

Now, this is not to say that algae will not feed on any available nutrients once they form. If nitrates and phosphates are in the water algae will then feed on whatever resources are available, but the presence of NO3/PO4 cannot by themselves cause the algal blooms to occur. This is another crucially important principle. If you change your mindset to the following formula-> "Light+NH4=Algae" you'll be on the right path. If you follow this path then the next path will be "how do I eliminate NH4 as much as possible?" One way is to make your plants as healthy as possible. Another is to directly reduce NH4 concentration levels by water changes.

Your high stocking level means that there is a large ammonia production via urine/feces and other organic waste. Doing frequent water changes removes large quantities of NH4 and organic waste. However if you don't feed the plants properly by providing large, stable quantities of CO2 and by dosing the proper quantities of nutrients such as NO3 and PO4 then your plants fail and actually contribute to the problem of NH4 buildup.

There is absolutely no point in blaming any algae problems on nitrate or anything else. If you have BBA this is telling you to fix your CO2 (or the distribution of CO2.) If you have BGA this is telling you to add more nitrate. No test kits can solve this problem for you. Algae is never confused, but we are often confused by all the myths, legends and optical illusions.

Fix your CO2 by either increasing the injection rate and/or improving the flow patterns in the tank (via additional powerheads or filter upgrades) and dose the appropriate levels of NO3/PO4/Traces. See the EI sticky thread for further dosing instructions.

Physical removal of the BGA and BBA is important - no doubt about that at all, but once removed it will only recur if you continue the same pattern that caused them to appear in the first place.

If you want to maintain such high stocking levels then it might be advisable to significantly upgrade your filtration.

Cheers,

 

A simple "test" for water circulation is to use what is in the tank - the plant leaves. Look at leaves all over the tank. Are they all moving in the water current? If not, you could improve the circulation, and that usually means adding more water flow rate, but it could be just improving the direction of existing flow.

Never forget that water circulation is greatly inhibited by stuff in the way - plant leaves again. If your tank, like mine at the moment, is overgrown with plants, there just isn't room for the water to freely circulate. When it doesn't circulate, the stagnant water around the leaves runs out of CO2 as it is consumed, and probably runs short on other nutrients too. So, water circulation is very important, and heavy plant growth is the major problem for water circulation.

Now, perhaps I will listen to myself and go prune my tank!

 

My pruning skills are primitive. I use long scissors to lop off plants about half way down, either plant the cut offs, offer them for sale, give them away or scrap them. Today I just finished "pruning" by violently pulling my willow leaf Hygrophila out. I love the plant, but it is like having a gorilla for a pet - a bit too big. My tank is slowly refilling with water right now.

 

Ceg,

Excellent explanation and reply.

IMO it shoud be put with either Dusko's Algae id thread or in a sticky.

Shane,

If the plants are growing well, cutting them shorter will not hurt them. Top cuttings look better for stem plants so cut the BEST 4-6" from the tops and replant these. They will grow new roots. Or if the stem has roots around a node, cut at that point and replant........

You don't have to trim every plant in a bunch..... esp as you prune more, it becomes more selective.

Also, pruning induces branching, so more bio-mass, so include in your dosing calculations....

Good luck.

 

Thanks Gerry. I firmly believe if we stick with the priciples that brought us EI we'll be able to diagnose whatever problems we encounter.

Shane, when I mention upgrade of filtration I refer to the whole enchilada. Filter size, quality media and flow rate turnover. George Farmer and I have started using the 10X tank volume filter rating as a filtration recommendation. Naturally this is not set in stone, just another "rule of thumb" that we find useful. Filters have a very optimistic rating because the vendors often rate the turnover based on empty media trays as well as placing the pump head very near the waterline so that the resistance is minimized. A fully loaded filter placed a meter or so below the water line normally only delivers 50%-60% of it's rating. When you add other factors such as backpressure due to adding CO2 diffusers, mulm and detritus in the trays the throughput is reduced even further.

So a 60 gallon high tech tank would get filter(s) which have a total rating of around 600 gallons per hour, which sounds exorbitant until you realize the actual delivered flow may only be 300 gallons per hour or so.

Extra filter capacity also means volume for filter media. The more filter media volume the more surface area there is for bacteria to colonize the media. This means a higher population of bacteria for NH4 removal. Quality of filter media is also important. I don't have any hard data to prove it so I have to say that I believe that the sintered glass media such as the Eheim Effisubstrat, or Fluvals equivalent have a higher surface are than say, sponge and definitely has higher surface area than plastic bioballs.

As the filter gets dirtier there is a likelihood that detritus clogs the pores of the sintered glass balls reducing the effective surface area and lowering the bacterial population. Theoretically a third or so of the media should be replaced every few months or so but I'm a cheapskate so I rarely do this.

As VaughnH says, you can tell if your distribution is OK by observing the plants to see what percentage of the leaves "sway in the breeze". If you have a much lower percentage of leaves behaving this way then this tells you that you need to rework the circulation in the tank and that would be one of your goals - to maximize the number of leaves that are affected by water flow. Consider using spraybars mounted on the back wall pointing forwards (depending on your sense of aesthetics). This is an especially good technique of delivering nutrients/CO2 to the carpet plants which are at a distinct disadvantage way down at the substrate level. If you are unable to add more filter flow then adding powerhead(s) in strategic locations would be the next best thing.

So lots to think about. I think you'll find that paying attention to flow/circulation is effective in helping to ease the negative effects of mistakes/weaknesses in the dosing/CO2.

Cheers,

 

It is certainly true for some plants, but not all of them. Some just sent out a single new shoot. Others send out multiple new shoots from every node below the cut. The willow leaf hygrophila I had liked to send out a kazillion new shoots, all of which would reach the surface the next day! OK, that is a slight exaggeration, but that is one plant that pruning really stimulates.

 

Yes I use these. They are pretty much the same type of sintered media. That means they are very porous and have very high total surface area internally and externally. I'm lazy and cheap so I hesitate to suggest changing out media every few months but that is the official line.

Remember that the bio-media isn't a chemical product so the expression "regenerate" isn't appropriate. The media is best thought of as house and home for bacteria. Dirt blocks the entry points so that neither water nor bacteria can enter. There is still surface area on the external side of the ball but the total population of bacteria that each ball can house when the pores are suffocated by trapped particles is sharply reduced. This may or may not matter so much if you have huge filter capacity with gallons of filter media though.

I reckon if you clean your filter regularly you can prolong the usefulness of the media. There is one huge deterrent for me in using bleach. That is, bleach kills bacteria. We're not interested in killing bacteria but removing the dirt that clogs the pores thereby blocking water entry and bacteria buildup inside these pores. If bleach soaks in and is trapped inside the pores I don't know how long it would take for the bleach to dissipate to allow bacteria to recolonize inside the pores and in any case, I don't think bleach actually dissolves the detritus all that well (it may just turn it white ). I can't think of any way to mechanically remove the trapped dirt, and I can't think of any way to chemically dissolve the dirt without leaving "bacteria unfriendly" chemicals behind.

I agree about the flow of the Eheim filters. Eheim seem to be more optimistic than most in regards to their filter throughput ratings. I have a couple of the big pro III filters but if I had to do it again I could easily opt for the Fluval equivalent which is much less expensive. I could still use the Eheim media inside the Fluval, or use the Fluval sintered glass media. Flow rate is king in my book now and the quality of filters over the years have improved to the point where there is very little to separate one from the other, so given a choice between two I'll now compare rated flow first, the other factors being secondary.

Cheers,

 

Hi shane,
One of the reasons I decided on the Pro III was the availability of the 500W heater in the 2180 model which meant one less "thing" to connect or to see. the tubing is 16/22mm and yes it does have a lever for adjustable flow - but I never use this lever except to close it in order to trap the suction while disconnecting the hose module when cleaning the filter body. Again, the flow is rated at 1700 liters per hour but with the canister filled with media, a Cal Aqua inline diffuser connected, and the pump head less than a meter below the waterline I measure the flow at around 800 liters per hour. The second unit is attached to an AM1000 and the flow rate is significantly less.

As I mentioned before, due to cost and lower actual delivered flow the FX5 might have been a better investment.

Reducing the diameter of any hose in the circuit will always reduce the flow rate because it back pressures the pump. The pump impellers would have to then rotate at a higher RPM to overcome this back pressure but it isn't configured to do that.

The pro III is a very good machine and the non-thermo version is less exorbitantly priced but just be aware that the FX5 has a higher flow rating and is less expensive. The ergonomics are different issue though.

Cheers,