Glass Tops?

[wolf pup]

I'm curious. I notice that it seems as if noone is using glass tops on their aquaria. I have a 125 that has gone through several incarnations and is currently moving towards a community/reef? tank. I have a canopy that I bought with the tank back in '97? Back then it was criminal to not have glass tops so I have used them ever since. I do have a 55gal sump in my basement now with around 800gph of flow. I would like to know why glass tops are a thing of the past. Gas exchange? Blocking light? Evaporation (Tempature control?) Thanks!

[ahullsb]

I think all of the above. I took mine off shortly after setting up my 55. I was battling heat issues, I think I was getting poor gas exchange, my tank looked dimmer, and I had to clean them all the time. It seems that netting or open top has been beneficial to my tank.

[Aquarist007]

I agree with all of the above. If the issue becomes the carpet surfing of some fish then you could use egg crate

This is not quantified by anymeans---but I have found that keeping the surface and first 4 inches of water churning by using power heads seem to discourage fish from that area.
I also feed by putting my hand in the tank underneath the locklines and releasing the food so it is quickly carried down.

Its kind of like the concept if you don't play on the rr tracks you are not going to get hit by the train.

[wolf pup]

Hmmm....I guess my next question would be what's the cheapest way to seal the canopy so it doesn't rot away without the glass tops. I'm also looking to retrofit a bunch of 39watt T5HO's into the canopy which would only put them maybe 4" above the water. Starting to wonder if I'm heading towards a nice big zap!

[Aquarist007]

not if grounded properly---and there are intank ground probes you can purchase.
The problem will be salt creep over the bulbs----you will have to take them out and clean them when it builds up.

[reefkrazy]

I dont use one. It helps with the gas exchage.

[msn711]

I will admit that those are all valid reasons why glass tops aren't popular. However, I still use glass tops on my tanks to keep the fish inside the tank. For gas exchange, I believe sumps are great for this. If any light is being blocked, I think it's rather insignificant. As far as the temp. issue, A fan blowing across the sump has solved this problem for me. Lastly, on cleaning the glass, I've just made it part of my routine weekly maintenance. I don't think it's that big of a deal. Just pointing out that if you want to use the glass tops, you can, especially if, like me, you already have them.

[Aquarist007]

Originally posted by wolf pup
I'm curious. I notice that it seems as if noone is using glass tops on their aquaria. I have a 125 that has gone through several incarnations and is currently moving towards a community/reef? tank. I have a canopy that I bought with the tank back in '97? Back then it was criminal to not have glass tops so I have used them ever since. I do have a 55gal sump in my basement now with around 800gph of flow. I would like to know why glass tops are a thing of the past. Gas exchange? Blocking light? Evaporation (Tempature control?) Thanks!

IMHO--that's not alot of flow for that size of tank---you should try for 15-20 times tank turn over per hour for lps corals and at least double that for sps corals.

You might run into heat/gas exchange problems if you use glass covers with that low a flow rate.

[wolf pup]

capn_hylinur,

I have heard many suggestions on turnover - generally as I understand it I need to look at my sump flow as a separate issue from a closed loop issue as pushing a great deal of water through my sump gives little reaction time for the fuge/skimmer/etc. Long before I move into lps or sps (right now its only a wlr) I would look into moving a greater "flow" within the tank. Or am I misintrepreting what I have been reading? I am new to the whole community/reef issue and want to learn before I make any mistakes but running 2500 gph through a sump seems odd...

(Edit) - I realize as I look back that I may have been unclear in my first post on "flow" - that is what is going between the tank and the sump alone.

[Kryptikhan]

hmmm. was just about to buy glass top....now im lost lol. is it good or no

[Aquarist007]

Originally posted by wolf pup
capn_hylinur,

I have heard many suggestions on turnover - generally as I understand it I need to look at my sump flow as a separate issue from a closed loop issue as pushing a great deal of water through my sump gives little reaction time for the fuge/skimmer/etc. Long before I move into lps or sps (right now its only a wlr) I would look into moving a greater "flow" within the tank. Or am I misintrepreting what I have been reading? I am new to the whole community/reef issue and want to learn before I make any mistakes but running 2500 gph through a sump seems odd...

(Edit) - I realize as I look back that I may have been unclear in my first post on "flow" - that is what is going between the tank and the sump alone.

you need both

from a filtration aspect you want to assure that phosphates and other dissolved organic compounds are constantly in the water column so they can be filtered out. Area of minimal flow in the tank can accumulate DOC's and cause problems with bacteria production(cyano) and algae growth. Power head within the tank help with this.
You'll find the mode answer on this site--that more flow(tank turnover) is better then less. The more water you put through your sump the more it can filtered--and with proper flow within the tank you are keeping a steady flow of DOC's past filter sock, protein skimmers and refugiums.

[Aquarist007]

Originally posted by Kryptikhan
hmmm. was just about to buy glass top....now im lost lol. is it good or no

in tanks with reduced flow rates--it is not a good idea---because some gas exchange occurs at the top layer of the water column and it can cause heat issues esp with metal halide lighting.

[Dr Begalke]

Gas exchange? Blocking light? Evaporation (Tempature control?)

I agree those are all reasons, but i think blocking light is the biggest factor... the others can all be compensated for in other methods.

If you run a PS, i don't think a glass top is going to suffocate your fish...

[Kryptikhan]

Originally posted by capn_hylinur
in tanks with reduced flow rates--it is not a good idea---because some gas exchange occurs at the top layer of the water column and it can cause heat issues esp with metal halide lighting.

ok so if we dont go glass top...then what? Reduced flow rates? i take it this depends on pump and pipe size?

thanks......

[lubyone1]

Clear spar varnish will work to seal your hood. It's what I used on mine.

[uscharalph]

I have purposely stayed away from jumpers.

[wolf pup]

lubyone1 - Thanks - is that a home depot/lowes item?

capn_hylinur - I really don't think I'm gonna try to run 2500gph through a 55gal sump 2 x 1" drains give me a theoretical 1200 gph flow and I would need to change a great deal of equipment to swap those to 2 x 1 1/2" or larger. I am on board (arrr capn - sorry couldn't resist) with the tank flow and this will probably be accomplished through powerheads which will also let me tune out dead spots.

The issue of blocking light intrigues me as I am planning on t5s. I'm thinking of mounting about 4" above water surface so I would want to shield the bulbs/reflectors from salt spray etc. soooo am I'm thinking I should leave the glass tops rather than buying glass to protect the lights (I'm doing retrofit so there is no fixture - a fixture would obviously eliminte that particular need)

My wife likes the house cool so temperature is not going to be a big issue. The pump room in the basement is downright chilly both summer and winter so I'll probably need to keep the heaters running during non light hours.

Gas exchange does leave me scratching my head. Dr B, I do run a PS (GS2 soon to have recirc mod) and there is a great deal of turbulance in the return section of the sump but what I am a little concerned of is creating a gas trap between the top of the tank water and the tops. I may see if I can borrow an air quality meter from work and do a couple of observations down the road.

[Aquarist007]

Originally posted by wolf pup
lubyone1 - Thanks - is that a home depot/lowes item?

capn_hylinur - I really don't think I'm gonna try to run 2500gph through a 55gal sump 2 x 1" drains give me a theoretical 1200 gph flow and I would need to change a great deal of equipment to swap those to 2 x 1 1/2" or larger. I am on board (arrr capn - sorry couldn't resist) with the tank flow and this will probably be accomplished through powerheads which will also let me tune out dead spots.

The issue of blocking light intrigues me as I am planning on t5s. I'm thinking of mounting about 4" above water surface so I would want to shield the bulbs/reflectors from salt spray etc. soooo am I'm thinking I should leave the glass tops rather than buying glass to protect the lights (I'm doing retrofit so there is no fixture - a fixture would obviously eliminte that particular need)

My wife likes the house cool so temperature is not going to be a big issue. The pump room in the basement is downright chilly both summer and winter so I'll probably need to keep the heaters running during non light hours.

Gas exchange does leave me scratching my head. Dr B, I do run a PS (GS2 soon to have recirc mod) and there is a great deal of turbulance in the return section of the sump but what I am a little concerned of is creating a gas trap between the top of the tank water and the tops. I may see if I can borrow an air quality meter from work and do a couple of observations down the road.

wolf pump--if your sump is in the basement it is easily done---I am running a 3600mag with 7 feet of head pressure it is producing 2200gph.
I started with exactly the same pump and flow rate you had--when I switched it made a huge difference in water quality.

[Aquarist007]

Originally posted by Kryptikhan
ok so if we dont go glass top...then what? Reduced flow rates? i take it this depends on pump and pipe size?

thanks......

I am a little confused here(LOL) What I think you are saying is that glass tops reduce the flow rate-----not so. Glass tops reduced the the area of gas exchange and heat dissipation on the top level of the tank.
Its not a problem if you have a sump and protein skimmer

[chatyak]

Originally posted by capn_hylinur
I am a little confused here(LOL) What I think you are saying is that glass tops reduce the flow rate-----not so. Glass tops reduced the the area of gas exchange and heat dissipation on the top level of the tank.
Its not a problem if you have a sump and protein skimmer

Good to know... I just ordered my glass tops for a 55 gal.... am planning on a 29 gal sump with over 1000+gph flow.

[DrBegalke]

Originally posted by wolf pup


Gas exchange does leave me scratching my head. Dr B, I do run a PS (GS2 soon to have recirc mod) and there is a great deal of turbulance in the return section of the sump but what I am a little concerned of is creating a gas trap between the top of the tank water and the tops. I may see if I can borrow an air quality meter from work and do a couple of observations down the road.

I'd be curious as to your results...
but look at this way, if you have an airstone (or PS) in a plastic cup of water... is the oygenation going to change much if you had plastic lid on top of the cup? I dont think so.. the amount of diffusion at the surface is small compare to all the microbubbles, turbulance, etc.

[Kryptikhan]

Originally posted by capn_hylinur
I am a little confused here(LOL) What I think you are saying is that glass tops reduce the flow rate-----not so. Glass tops reduced the the area of gas exchange and heat dissipation on the top level of the tank.
Its not a problem if you have a sump and protein skimmer

So putting a lid on my sump if i have a glass top is suicide? gas exchange etc..........cant we just put crate for lid?

[chatyak]

I wouldn't put a lid on your sump...tank yes but sump no.

[Aquarist007]

Originally posted by Kryptikhan
So putting a lid on my sump if i have a glass top is suicide? gas exchange etc..........cant we just put crate for lid?

why would you be putting a glass top on a sump? Glass tops are usually used for carpet surfers--and I can't see you having any fish in the sump

[chatyak]

Originally posted by capn_hylinur
why would you be putting a glass top on a sump? Glass tops are usually used for carpet surfers--and I can't see you having any fish in the sump

A sump surfer